Once you setup your Android device and link it to a Google Account, the account you used becomes the central account for GTalk, Gmail, Maps and other Google services. But what if you want to change the account? The Android OS doesn’t provide a way to simply enter new account information. Here’s what you’ll need to do.
If your device isn’t rooted, the only thing you can do is perform a hard reset on the device. You can normally do this under Settings > Privacy > Factory data reset. Doing this will wipe all data and settings from the device.
Unfortunately, if you really need to change the main Google account, this is the only option unless you gain root access. If you wish to gain root access, you’ll have to research how to root your specific device. Many devices can be rooted using Gingerbreak.
If you have root access to your device, you’re in luck. There is a handy trick you can use to change the main Google account without performing a hard reset.
2. Open Root Explorer and select Allow to allow root access if prompted.
3. Navigate to the /data/system directory.
4. Tap and hold the accounts.db file, then select Rename.
5. Rename the file to accounts.db.old to make a backup of the file.
6. Restart your Android device.
7. Once the device restarts, open an app that requires a Google account such as Market, Gmail or GTalk. You will be prompted to create a new account or login using an existing account. That’s all there is to it.