Really really newbie question..

[niranpr]

I use Bitcoin Wallet on Android.
I can't find private key. Where is it..? 

[Signus]

You need to have a wallet already created since I don't think the app will create one for you. Either by going to Coinbase (new) or creating one via the normal methods. Check out http://bitcoin.org/en/choose-your-wallet. Once you have a wallet you get a wallet "address" this is the code that the Android app uses to monitor your wallet, depending on the method you use to obtain a wallet.

New services like Coinbase maintain your wallet online while the original method involves downloading your Bitcoin wallet and updating it via an app on your desktop.

[angos]

thank you, let me try 

[angos]

i got it, bitcoin wallet on android generate bitcoin address and private key for me, but it didn't show private key.
only way to use private key is to export it as a text file. there is a menu named "backup keys" hidden in the app.