Display the Login name or email in the Banner/Header of the App so we can easily tell what account we are logged into
I should be able to tell which account I am signed by just looking at the web or Android apps (I can't speak for iOS). If that is seen as a privacy issue perhaps an icon could be used to differentiate.
As it is I have to go to settings, or click on the To: header in an email to get the address to pop up
Unfortunately there is not enough space left for the login name in the apps.
For the desktop browser version we will implement this solution: http://tutanota.uservoice.com/forums/237921-general/suggestions/8708773-display-account-mail-address-in-browser-s-title-ba