FREE - In Google Play
FREE - in Win Phone Store
When viewing new messages (eg . http://www.chess.com/home/view_message.html?id=#####) it'd be convenient to have the page automatically go to your next unread message when you press the Archive button, instead of having to manually click Next yourself.
I just discovered that there's a limit for the Archive function. Gmail has me thinking there's no such thing as "limits"!