How to block a phone number in Android?

Occasionally, there is some situation that you do not want to answer calls from a particular person. So, many cellphones provide "blacklist" function -- you put a phone number into this blacklist, and your phone will ignore calls from this number.

It seems that my Android phone does not directly support this function. But, you can get pretty much the same result by using the following trick: open your phonebook, edit the contact you want to block, choose "Send calls directly to voicemail", done!

I heard the latest Android (Android 2.2?) has the blacklist function. It will be a useful function to many users.

Behavior-targeting of Display Ads

This past week, Google announced the quarterly report. Display Ads and Mobile become a significant part of Google revenue source. For Display Ads, Google revenue is $2.5 Billion in the next 4 quarters. Excluding fee paid to partners, it is estimated that Google will earn $2 Billion in the next 4 quarters.

Display Ads was actually born earlier than Search Ads. But Search Ads is much more effective than Display Ads because it captures user intent. That's why Google Search Ads is so successful.

In the past few years, however, display Ads is catching up because behavior-targeting technology. Among behavior-targeting technologies, data is the core part. With user intent data, display ads can be much more effective.

According to a report, Rocket Fuel can lower their eCPA as large as 64%.

Here is the breakdown for different verticals:

• Automotive: 64% lower effective cost per action (eCPA)
• Retail: 24% lower eCPA
• Travel: 37% lower eCPA
• CPG: 50% lower eCPA

I believe that display advertising has a bright near-future as long as it deals with privacy issue well.

How to improve the battery life of your Android phone?

I bought a new Android phone, mainly because I’m not quite happy with the battery life of my old phone. After searching in the market for a while, I noticed Ericsson Xperia X10. The ads says that its battery is rated at up to 8 hours of talk time, and up to 415 hours (17+ days) of standby time. So I bought it.

It is a very cool cellphone. But I noticed that I had to charge the battery almost every day, without any heavy use. It is far from the advertised “415 hours (17+ days) of standby time”. So I did some research and tried to improve the battery life of my new phone. After some tune-up, my phone now can stand by for almost 5 days without heavy use. It is a great improvement, isn’t it? Although it is still far from its ads.

So, what did I do? I did the following things:

1. Turn off its wi-fi, bluebooth and gps service when you do not use them. It seems that this is the most critical part. From the “battery usage” provided by Android, I noticed that wi-fi really used a lot of battery.

2. Download and install “Startup Auditor” application from Android Market. You can use this application to prevent some applications from running when you turn on the cellphone. Your cellphone usually will start up a lot of creepy (and useless) applications when you turn it on.

3. Turn of the Synchronization function of your gmail and facebook applications. Frequent synchronization uses too much battery.

4. Download and install “Andvanced Task Killer” application from Android Market. You can run this application from time to time and kill some applications. When you open an application and then return to the “homepage” of Android, this application is usually still alive and running in the background.

If you are not happy with the battery life of your Android phone, you should try those tricks out!

from semi-smart phone to smart phone -- my two-year experience with AT&T

My current cellphone is an LG Vu from AT&T. I bought it at year 2008, just before the first iphone was shipped. I am quite happy with this phone -- it has all necessary functions I need (bluetooth, internet browsing, big screen, friendly user interface, etc). But after two years, the battery deteriorates a lot and I have to charge it almost every two days. Last week I decided that it was time to get a new phone, so I ordered a SonyEricsson Xperia X10. This is a very powerful Android phone.

A lot of things happened in the last two years, especially in the IT industry. From LG Vu phone to Xperia Android phone, I clearly see the changes. Two of them are especially interesting:

1. My old LG phone has an application called “AT&T Mall”. You can browse and buy music, pictures, games and applications from AT&T through it. Sounds familiar? It is very similar with Apple’s App Store and Google’s Android market. But it did not get success as big as those two. In my new Xperia Android phone, this “AT&T Mall” is gone and now it is Android market.

2. My old LG phone has an application called “MySpace Mobile”, which allows you to access your MySpace account easily. Remember MySpace? Now everybody is talking about Facebook. Accordingly, I can not find MySpace application in our Xperia X10 now (of course, you should be able to install a MySpace application through Android market). Instead, Xperia has a Facebook application supporting your addiction to Facebook.

What do those tell us? A good idea does not necessarily lead to good business, and the roaring wave of internet business is so unpredictable.

I’ll post a review on my Xperia phone when I get more experience with it. So, stay tuned :-)

Cookie of WiFi at Starbucks Coffee

Recently, Wall Street Journal has a series of articles about behavior targeted advertising industry called What They Know. I sometimes go to Starbucks to use Internet. A few months ago, Starbucks decided to offer free WiFi inside the coffee shop. I am curious what cookies (browser cookies, not eatable cookie) Starbucks WiFi tries to set in your user browser if you use Starbucks free WiFi.

So I enter a Starbucks coffee chop, clear all Internet browser Firefox cookies, visit the wikipedia.org website (WSJ reports that wikipedia does not set any third-party cookie on the user browser), which will be redirected to Starbucks WiFi start page. I accept the Starbucks Term of Use. Then I check the cookies in the browser and find cookies from 7 sites are set. 2 of them are from Starbucks site, i.e., coffeblogs.starbucks.com, and starbucks.com. The other 5 are from third-party, google.com, facebook.com, addthis.com (sharing and bookmarking service), ads.jiwire.com (mobile advertising), and tags.jiwire.com.

Overall, I think behavior-targeted advertising, a.k.a. personalized ads, is a good thing to Internet. It's a win-win-win for users, publishers, and advertisers. For users, they will see more relevant ads and coupons. So ads will become more useful and attractive to users; for publishers, they will make more revenue from advertising, thus produce more high-quality contents, survive and thrive; for advertisers, they will reach users what they really target at, thus improve their ROI (Return On Investment). But I agree that the Internet advertising industry should develop a better way to provide transparency and control to Internet users, although I think 90% and maybe even higher percent Internet users do not really care about behavior-targeted advertising and privacy.

Many people are happy about the free WiFi offered by Starbucks. I hope Starbucks can continue this free service by making some revenue from behavior-targeted advertising.

What is Droid Incredible and EVO 4G?

Today, Apple CEO Steve Jobs unveiled a new version of iphone, although it had been leaked by Gizmo in April. Video chat is the new feature not leaked before. On the other smart phone camp, Android, there are some also hot products released recently. One is Droid Incredible on Verizon network. Last Friday, when I visited Palo Alto Verizon store, it was told to be sold out. If you order that day, you may get it in late June. It should be mentioned that Droid Incredible and Droid, released around holiday season last year, are quite different. For example, Droid Incredible has no physical keyboard while Droid has. Moreover, Droid is manufactured by Motorola, and Droid Incredible is manufactured by HTC. Droid Incredible is more like Nexus One than Droid.

The other is Sprint EVO 4G, which uses Springt 4G network, the first 4G wireless network in US. Interestingly, both EVO and Droid Incredible are manufactured by HTC, who also manufactures Nexus One and the very first Android phone G1. It should be mentioned that HTC is not Foxconn, which manufactures iphone, although both HTC and Foxconn are companies in Taiwan.

I also heard that right now the number of sold Android phones is larger than the number of sold iphone number, which is not surprising since there are many versions of Android phones on the market, while there are one or two versions of iphone on the market.

iPad is not an e-reader

Apple's iPad will go on sale in early April, very soon. The comments about iPad is mixed. One thing I definitely think about iPad is that iPad is NOT an e-reader as Amazon's Kindle, Sony ereader, or Barnes Noble's Nook. It may be an e-reader in the future, but not right now. I would consider iPad as a mixture of TabletPC and Netbook (for iPad with wifi functionality).

The reason I think iPad is not e-reader is mainly iPad does not use e-ink or other alternative technology to make reading experience much like reading physical books.

iPad uses LCD technology. I agree that LCD is better than e-ink in that 1) it is colored, not just black and white, so we can view nice pictures, play games, etc. 2) it has multi-touch screen. I hear that in the near future e-ink could not support neither color nor touch screen.

But an e-reader should have two basic features as a reading gadget. One is to make eye more comfortable and reading experience is like that of reading a physical book. iPad uses LCD, much better than CRT. But as an avid reader, I still feel my eye is tired after reading pdf on LCD for an hour. I have no such feeling after reading a physical book for an hour.

The other is that readers can use ereader to read it outdoors, such as during a picnic in a park, or when relaxing at a sunny beach. Do you have the similar experience with your smart phone that, in the sunshine, it is very hard to find who is calling you, what is written in a friend's email, or take a look at the picture you just shot? E-reader should let you read anywhere and anytime.

What is WAP?

Although smart phone competition among iPhone, Droid, Nexus One, Blackberry, and Palm Pre is red hot, not everyone has a smart phone and actually most people still use simpler and much cheaper phones. According to New York Times article Firms Selling Apps for Simple Phones,"roughly 82 percent of cellphones in use are limited-function phones, the kind that typically sell for less than $50 or are given away with a two-year service contract."

These traditional phones can also access Internet. In Asian coutnries like China, WAP is still very popular to access Internet. So what is WAP? Here WAP stands for Wireless Application Protocol (WAP), not Wireless Access Point. It is a suite of protocol of wireless communications. It usally runs on 2G mobile network, like GSM, CDMA, and GPRS.

What is the difference between WAP and GSM/CDMA? Using analogy, some people consider GSM/CDMA as highway and WAP as vehicle on the highway. Using more technical terms (TCP/IP and OSI), GSM/CDMA provides lower level data link/physical layer and WAP provider higher layer (UDP, HTTP) and some a markup language WML (Wirless Markup Language), similar with HTML.

People can use WAP to browse websites, check emails, track sports scores, etc. In Japan, NTT DoCoMo offers i-mode as a competitor of WAP. But KDDI and SoftBank mobile use WAP.

Do not be confused about WAP and WAPI. What is WAPI? WAPI stands for WLAN authentication and Privacy Infrastructure and is the Chinese version of Wi-Fi. Chinese government required handset manufacturers to support WAPI if Wi-Fi is supported on cell phones. In 2009, it was a big issue when Apple iphone planned to enter Chinese market. When China Unicom introduced iphone in China later, iphone has neither Wi-Fi nor WAPI functionality, although it is reported that iphone with Wi-Fi and WAPI will be on the market in 2010.

BTW, what is the difference between WAP and Wi-Fi? Again, Wi-Fi is a data link layer and provides a data highway so that data can be communicated using TCP/IP protocol. In some sense, WAP can be considered as the counterpart of TCP/IP, and GSM/CDMA, which under the WAP, as the counterpart of Wi-Fi.

How to change primary email account for Android phone G1 Dream?

Android phone G1 Dream has only one email account associated with Gmail app. When you start pre-installed Gmail app (not Email), you can directly read your email without login and get notification when you've got mail. This email account is also associated with other applications like Contacts (sync with your email account) and other Google apps. When the phone ownership changes, e.g., you want to give you G1 Dream phone to your spouse since you just bought a Droid, the email account needs to be changed. How can I change the primary email account? How can I remove existing contacts to protect privacy? How can the new owner import his contacts?

Some people suggest we do factory data reset. It is not necessary. Here is how you can do it without factory data reset.

1) Go Menu -> Setting -> Applications -> Manage applications.

2) Gmail Storage -> Clear data.

3) Gmail -> Clear data.

4) Google Apps -> Clear data.

5) Google Search (enhanced) -> Clear data, then your existing contacts and your former email account are removed.

6) Restart Gmail, which will ask you to set up your Google mail account. Now you can set up a new gmail account. Then emails and contacts will be synchronized and shown up shortly.

However, it does not work for Nexus One. On Nexus One, you will not see Gmail storage, Gmail, Google apps, or Google apps item on Menu -> Setting -> Applications -> Manage applications. But for Nexus One, you can associate several email accounts with Gmail app. Here is how you add multiple email accounts to Gmail application on Nexus One.

1) Go Menu -> Setting -> Accounts & sync.

2) Add account and set up another Google email account following the wizard.

3) When you start email, you have one primary account and emails associated with it to read. When you view email, you can select Setting -> Accounts and pick your another email to check emails associated with your other email accounts.

Wireless Signal Series: How to disable mobile carrier's data service on Android phone

Although smart phones like Android phone can use mobile network carrier's data service (e.g., 3G, Edge, or GPRS data service) to surf Internet, people sometimes do not want to use mobile network carrier's data service. For example, in some phone plans, mobile network carrier charges the consumer based on usage. When the wi-fi is freely available to the consumer, he wants to explicitly disable mobile network carrier's data service to avoid unnecessary usage charge and instead use the free wi-fi to surf Internet or check emails.

It should be mentioned that although we disable mobile network carrier's data service, we can still use mobile network carrier's voice service to make phone calls.

There are at least two methods to easily do this. One method is as follows.

1) Menu -> Setting -> Wireless & network -> Mobile network -> Access Point Names (APN).

2) Click the available APNs (T-mobile US, epic.tmobile.com for me).

3) Select APN.

4) Update a random prefix or postfix to APN name, e.g. change epc.tmobile.com to x-epic.tmobile.com or epic.tmobile.comx.

5) Click OK. Then the data service should be disabled.

The other method is to use APNDroid app.

1) Install APNDroid from Android market.

2) Start APNDroid.

3) Click Off/On button to disable or reenable mobile network carrier's data service.

Does cell phone radiation affect human health?

San Francisco city is debating whether to require cell phone sellers to put a label about the amount of radiation levels emitted by cell phones on the cell phone. State of Maine also has a similar bill in work. Increasing amount of people in the world have at least one cell phone, increasing percentage of cell phones are smart phones (with more wireless signals, mobile network, wi-fi, bluetooth, and gps signal), and cell phones use the same radiation as microwave uses. It becomes a hot issue whether cell phone radiation affect people's health, particularly brain health.

Check wikipedia article Mobile phone radiation and health,
you can see that a lot of research has been done. From these research works, however, no convincing evidence proves one way or the other. Some research concludes that cell phone radiation is harmful to human health, some research think the cell phone signal is too weak to be harmful, and other research concludes that phone radiation is beneficial to the health.

If you have concerns about the potential danger of cell phone radiation, you may consider methods to disable some wireless signals, or use headset during the phone conversation.

BTW, although it is questionable whether cell phone radiation affect your health, it is very clear that overusing cell phone (like texting and calling during driving or walking) is a danger to public safety.

Wireless Signal Series: What is Airplane mode on Android phone

Airplane mode on Android phone is very useful to me (airplane mode also exists for other types of smart phones). You can go Menu -> Settings -> Wireless & Networks (for Android 2.1, Wireless controls for Android 1.6) -> Airplane mode to check/enable or uncheck/disable Airplane mode.

If you check Airplane mode, you will disable all wireless signals including mobile network signal (voice and data), wireless signal, and bluetooth (GPS signal still works). So you can not make or receive a phone call, or use 3G signal to surf Internet. Why is airplane mode useful? Intuitively, you need to check airplane mode when you are on a flight. But it is more than that. Some people put their Android phone in the bedroom at night. They need to check airplane mode before going to bed. Otherwise, they may be awaken by the phone call or incoming email notification. Airplane mode is also useful when you bring your phone to a meeting room, movie theater (Silence is Golden), church service, etc.

There is a difference about airplane mode for Android 2.1 (Nexus One uses Android 2.1) and Android 1.6 (G1 Dream uses Android 1.6). For Android 2.1, after you check airplane mode, you can still enable Wi-Fi (Menu -> Setting -> Wireless & Networks -> Wi-Fi) to surf Internet (but you can not enable bluetooth); for Android 1.6, after you check airplane mode, you can not enable Wi-Fi (can not enable bluetooth either). I do not know the change is according to the design or by accident.

Wireless Signal Series: What are wireless signals on Android phone

Smart phones like Android phone usually receive three or four wireless signals. People is easily confused about these signals and puzzled about how to disable these wireless signals.

Here is some description about what wireless signals are on Android phone and other smart phones.

1) Mobile network. This is the signal from mobile carriers like Verizon, AT&T, T-mobile, and Sprint. You need to pay these carriers to use this signal. Based on mobile network signal, there are voice service (phone call), text message service, and data service. For the data service, there is 2G and 3G network signal. For Android phone, you can set them from Menu -> Wireless & Network -> Mobile networks.

2) Wi-Fi. This is the signal from your home wireless router, your company wireless data network, wireless network in public libraries, hot spot in cafe shops, bookstores, car service waiting rooms, airports, etc. You can use Wi-Fi to access Internet. More and more places offer Wi-Fi signals, free or not. For example, in November 2009, Google announced that it offers free Wi-Fi in 47 airports and on Virgin America airplanes. For Android phone, you can view what Wi-Fi signals are available from Menu -> Wireless & Network -> Wi-Fi settings.

3) Bluetooth. This is a short distance wireless signal. You can use it to connect with laptop or car with bluetooth functionality to transfer data. Or you can use bluetooth headphone to make phone call when you drive (strongly discouraged!). For Android phone, you can view bluetooth setting from Menu -> Wireless & Network -> Bluetooth settings.

4) GPS. This is a wireless signal sent from satellites about your phone location (latitude and longitude) about the phone. It's free. But sometimes it may be battery power consuming.

How can we disable all these wireless signals or individual wireless signals on Android phone?

1) To disable all signals (except GPS signal), use airplane mode. Menu -> Wireless & Network, check Airplane Mode. It disables phone and data service provided by mobile carrier, Wi-Fi, and bluetooth. But it does not disable GPS signal. You want to need this because you are required to do so on the flight, you are sitting in a meeting room, or you put your phone besides the bed, but do not want someone to interrupt your sleep by phone call or incoming email notification. Read this article for more information about airplane mode and airplane mode difference between Nexus One ((Android 2.1)) and G1 Dream (Android 1.6).

2) To disable GPS signal, go Menu -> Location & Security settings, and then uncheck Use GPS satellites. You want to do this because you want to save battery life.

3) To disable bluetooth signal individually, go Menu -> Wireless & Network, and then uncheck bluetooth. You want to do this because 1) you never use the bluetooth signal, like me, or 2) you are concerned about the bluetooth radiation.

4) To disable Wi-Fi signal individually, Menu -> Wireless & Network, and then uncheck Wi-Fi. You want to do this sometimes because you want to save battery life.

5) To disable data service provided by carrier, you can install an app called APNDroid (APN stands for Access Point Names) to do this. You do this when you want to use Wi-Fi rather than 2G/3G signal provided by mobile carrier to surf Internent. Why do you want to do this? a) In some phone service packages, data service is charged according to your usage. So when Wi-Fi signal is available, people want to use Wi-Fi signal to surf Internet for free instead of pay usage fee to mobile carreirs. b) In many cases (not always), Wi-Fi data transfer speed is higher than 3G mobile network.

Update on January 19, 2009: add a link about airplane mode.

How can I copy and paste text on Android phone

Many times when I read news article using Android phone browser, I want to do a search on some text in the article. So how can I copy text in the browser and paste it in the search box? Here is a method.

For copying text when you browse web pages, push the menu button on the bottom of the phone, Select More menu item, then select Select Text menu item (Pay attention that the menu item is not called Copy, so do not look for Copy menu item), now you can use your finger select the text you want to copy. The text is copied to the clipboard. I find it is hard to select the exact text you want to select. Many times, I over-select text.

For pasting text in the search box to do Google search, you touch and hold the search box on the screen for a while, a context menu jumps up. You select Paste menu item, the text will show up in the text box. Then you can do a Google search.

This method has an asymmetry. I copy text using the hardware menu button on the bottom of Android phone display; I paste text using the context menu by touching and holding the text box on the screen. So it will take time for people to figure out this method. I hope there is a simpler way to copy and paste.

How to donate to Haiti by text message?

On Tuesday January 12, 2010, Haiti was hit by a catastrophic magnitude 7.0 earthquake. US government and people show great sympathy to their poor Caribbean neighbor (the world does the same thing). A new phenomenon in relief effort, different from tsunami 2004 relief effort, is that people use text message to make donation to Haiti.

How can we make a donation to Haiti by text message? It's very simple. Send HAITI to 90999, then you make $10 donation to American Red Cross relief effort in Haiti. It was reported that until 1:00p.m., January 17, 2010, text message donation to American Red Cross relief effort had reached $7 million. An impressive number!

American Red Cross does a great job to make this innovative way to raise fund. Verizon spokesman Jeffrey Nelson commented "These are donors who are typically the hardest to reach: young people. They're reacting to something that affects them and realizing their few dollars can make a difference. Texting has opened up a whole new world for philanthropy." American Red Cross also does a great job to market this donation method. Over the weekend when I watched the football game, I saw the advertisement on both CBS and Fox about text messaging to make donation to American Red Cross many times. TV audience know and execute this method extremely easily.

I searched around and could not find other humanitarian aid organizations such as Mercy Corps make similar donation push using text message. I hope that they will adopt this method soon.

$10 donation will show up on your mobile phone monthly bill. In Can we use mobile phone to pay?, I discussed that there will more and more chances that we need to use mobile phone to make payment. Right now, mobile phone carriers just passively put these donation payment on the monthly bill. It is actually a golden opportunity for carriers to make the new mobile payment service besides the voice and data service.

On TV, I saw some helicopters in Haiti drop package down. Even in poor countries, many people have cell phones now. Maybe donation cash can be distributed to these poor people directly through cell phone directly so that the cash can be delivered to people in great need. It is a direct donor-to-donee donation.

Update on January 18, 2010 : The WSJ article Quake Sets Back Haiti's Efforts to Improve Telecommunications reports that 35% of 9 million people living in Haiti have mobile phone, up from just 5% in 2006. So the mobile phone may play a role in donation such as the aforementioned direct donor-to-donee donation.

Where to buy a nexus one

A friend asked me the feedback of Nexus One usage. I highly recommended him to buy one. Then he said no retailer stores sell Nexus One yet. I told him that it is being directly sold to consumers at http://google.com/phone. I guess that most consumers are accustomed to buying cell phone at local Wireless shops or online retailers like Amazon. Moreover, they do not know Google actually sells something to consumers directly. Most stuff Google offers to consumers is free.

Another friend complained to me that in order to buy Nexus One, a Google Checkout account is needed while his Checkout account has been suspended because it is judged as a spam account. It's true that you need to set up a Google Checkout account which associates the bank account or credit card, like paypal. Unfortunately, there are not many people using Checkout compared with paypal. It would be better to accept Paypal, credit card, or debit card payment directly as well. As a retailer, the customer service is the key, as told by Zappos co-founder Tony Hsieh.

So there is a way to buy a Nexus One: visit http://google.com/phone or click here to buy it directly. You can buy an unlocked phone for $529 or a phone with two-year contract with T-mobile for $179. For the payment, you need to set up the checkout account if you have not, just associating your bank account or credit account with it. It is a pretty easy step.

Can we use mobile phone to pay?

A year ago, I watched some videos which show in South Korea, people use mobile phone to pay in shopping malls. Mobile phone works as an ATM card. This case shows that mobile payment is possible in rich countries. On September 24, 2009, the cover story of magazine Economist is the Power of Mobile Money, which reports the extensive usage of mobile phone in the poor world. Mobile minutes work as currency in some area. But in USA, people have not use mobile phone to pay yet. I expect that it will change soon.

With popularity of smart phones like iphone and Android-based phones, more and more transactions are made through the mobile phone. So mobile payments is needed. Paypal has an app on Android market. It has a simple interface. Some reviewers complain that users need to log in every time they use it. I think it is for security reason. I do not mind this small inconvenience. Think about the consequence if the cell phone is lost and some one somehow passed the security pattern.

There are some mobile payment startups which make mobile payment without banking account or credit card. Instead, they make mobile payment show up on the monthly cell phone bill directly. Boku and Zong are two rivalry in this mobile payment arena. I expect that mobile payment will become more popular in USA this year. But it depends on how people accept the mobile payment and how smart phones and mobile apps usage grows quickly.

How to find lost Android cell phone?

Mobility of mobile phone means you can use cell phone anywhere; but it also means you can lose your phone anywhere. One friend lost his Nexus one phone few days after he bought it. The market price is $529 for an unlocked Nexus One. What a loss! So how can we find a lost cell phone?

I found that there is a good Android application to help people find the lost cell phone. It is called Contact Manager. You search "Contact Manager" on Android market and install it. After the installation, start the app to set it up. From the contact list, you find a friend or relative. The contact (name, phone number, email, etc) of selected person will show up on the locked screen (right, the security pattern will be squeezed). If some nice guy find the phone, he can find the contact on the locked screen and return it to your contact. Do not select yourself since your phone will be in the hand of the guy who finds the phone. One drawback of Contact Manager app is that besides the security pattern squeeze, the Clock app screen also gets a little messed up.

Contact Manager app can help you find the lost cell phone if the guy who finds the phone is nice. How about if the guy is not nice and want to hold it? Your contact will never receive the call from the guy. Or how about if phone is lost on the shoulder of a road and no one has picked it up? Is there a way to let you proactively find your own cell phone. There is. Another Android app called Pintail can help. You can search "pintail" on Android market and install the app. After the installation, you select a PIN number. If you lose the phone, you can use a friend's phone to send a message locate PIN to your phone. After receiving the message, pintail will reply to a message with the phone location information (a Google map link). Then you can retrieve the phone there. If no one has picked up the phone, you can locate it and get it back. If someone else holds it, you can nicely ask them to return it to you. However, Pintail may have two problems. The first is the guy who finds the phone can easily change the PIN number of Pintail app. So your friend may not reach your lost phone if the guy changes the PIN number. The second is that if the phone is lost indoors, GPS signal is weak or not accurate (the error with 100 meters is normal.) So you still could not get the location of your lost phone.

How about when you locate the phone, someone holds the phone and does not want to return it? You need to call a policeman and show your proof. What proof can you have? IMSI and IMEI. You should write them down when you first get the phone.

To summarize, the first thing you need to do when you get a Nexus One or any Android cell phone, is

1) Write down IMSI and IMEI

2) Install Contact Manager

3) Install Pintail.

I heard there are some similar apps on other platforms like blackberry. But I never try it.

What is Nexus One memory or storage?

A friend complained to me about the limitation of how many applications can be stored on Nexus One because of limited storage. I am a little surprised about it. I thought Nexus One is a pretty powerful gadget with 1G CPU, 1G memory, and 4G SD card. So I did some studies about it. Here is the study result.

Nexus One has 512M RAM, 512M flash memory (a.k.a, internal phone storage), and 4G default microSD card. SD card can be upgraded to up to 32G.

You can find how much storage available using the following action sequence.

Home Screen->Menu->SD card & phone storage

You can see "Internal phone storage" (164MB for me) and "SD card" (3.57GB for me). Although I installed less than 10 apps so far, the internal phone storage has only 164MB left. Even with the brand new Nexus One phone, only 190MB out of 500M flash memory is available for app installation.

Currently Android app installation can only be put on internal flash memory because of security or privacy reasons; but the data used by app can be put on SD card. Also it was announced that soon app installation can be stored on the SD card.

So it is true that there is some storage limitation. But the issue will hopefully be solved soon.

What is the difference between Nexus One and Droid?

Today, Google introduced Nexus One, which generated a lot of excitement. I like to see the competition in smart phone market, which speeds up smart phone innovation and benefits consumers.

On October 30, 2009, Verizon released Droid. There is still a lot of commercial to promote Droid, even when I watched NFL game this past weekend. Droid is probably the most discussed Android OS-based cell phone before the release of Nexus One and is still hot in the market. Thus it is natural to ask what is the difference between between Droid and the newly released Nexus One. Here is some difference.

1) Branding: Nexus One is designed by Google directly (manufactured by HTC); Droid is designed by Motorola.

2) CPU: Nexus One uses 1GHz Qualcomm Snapdragon processor; Droid uses Texas Instruments' TI OMAP 3430 processor, which runs at 600MHz .

3) Keyboard and Trackball: Nexus One does not have physical keyboard. It has touch-screen soft keyboard; Droid has one physical slide-out keyboard and touch-screen soft keyboard. Nexus One has a trackball; Droid does not. Instead Droid has panel to move around.

5) Software: Nexus One runs on Android 2.1 version; Droid runs on 2.0.1 version. There are some difference, but not significant. Both OSes can be upgraded continuously.

6) Carrier: Nexus One is unlocked. You can use whatever network you like. Currently it has only GSM version. So it can be run on T-mobile or ATT network. A CDMA version Nexus One will be released this spring, which can be run on Verizon and Sprint network; Droid is the locked phone and is exclusively run on Verizon network.

It is exciting to see the release of Nexus One. It's interesting to see how consumers react to Nexus One. Overall, I think 2010 is the key year for Android-base cell phone.

BTW, if you want to buy Nexus One, you can buy from Google website directly.