My stock iPad mail icon goes to home screen
MY stack mail icon goes black & then goes to home screen. I've tried on/off & reset
iPad 2, iOS 8.3
Always begin troubleshooting issues with this standard progressive three step process: Restart, Reset, and Restore
Start by restarting your iPad. Press and hold the power button until you see the red slider. Slide to turn off the iPad then power it back on.
If that doesn't work, then you can try resetting your iPad by simultaneously pressing and holding the Home and Sleep/Wake buttons until you see the Apple Logo. This can take up to 15 seconds so be patient and don't release the buttons until the logo appears. Try one again again to see if the problem persists.
If it does, Use iTunes to restore your iPhone, iPad, or iPod to factory settings - Apple Support