I have 3 email accounts linked to the default mail app on this phone and now its lagging really bad and sometimes I get a black screen then the app closes. I've tried to close the app from the multi-task screen, force quit from the settings, restarted the phone and its still lagging really bad. I've pretty much given up on this default app and am using just the gmail app but not all of my emails are gmail. Is anyone else experiencing serious lag with the default mail app on this new HTC One?