Question

What is the Keystore files and why we need these files ? Also is it necessary to have a keystore files before publish our application in the android market ?

Please provide me some useful information regarding this .

Answer 1

See there are 2 types of keystore files we can have while developing android app:

1. Debug keystore (which is default, whenever you run the app either on emulator or device at that time APK generated is with this default keystore)
2. Private keystore (which is must for uploading app on market, so before uploading APK on market you must have to sign this APK with private keystore)

Note:

1. You can’t upload app on market using Debug keystore
2. You must have Private keystore to upload app on market
3. Once you have uploaded app on market and if you want to release Update to any existing app then you must have the same keystore by which you have uploaded application. One more important thing is that if you lost this keystore or forget password then you never be able to release update to that application.

For example:

Here’s an example of a Keytool command that generates a private key:

$ keytool -genkey -v -keystore my-release-key.keystore
-alias alias_name -keyalg RSA -keysize 2048 -validity 10000

More information you can read here: Signing Your Applications