To delete an account from TweetCaster on your Android phone, long-press the account icon in the dashboard. You will then see a popup menu with a "Sign Out" item.
Tap "Sign Out" and the account will no longer appear in TweetCaster. You can re-add the account by tapping the Sign In "+"
- Or -
Tap the menu and select Settings --> Accounts and thehn tap the account you want to remove then tap "OK" tap anywhere onscreen other than the dialog box to cancel.