Sale has ended but you can still get this app.
Download SwitchMe Multiple Accounts Key Now
SwitchMe Multiple Accounts Key

Official Description

This is the Key for SwitchMe - it unlocks all security features in the main application but does nothing on its own. It will be invisible in the app drawer, but can be uninstalled via the Manage applications interface.

As featured on Engadget, Lifehacker, XDA Developers and many more!