Most recently swiping an email would leaves a 'ghost' unclickable email in the inbox. Did no one test the main focus of the app? Prior to that they pushed out a release that crashed every time I opened it until I figured out how to delete my existing settings database.
Yesterday I tried to open it and it just told me "The app has been disabled" and refused to log me in.
They also broke integration with OSX. You can't set the app as your default client, so when you click on an email address, Apple's Mail app opens instead.