Re: Gmail has stopped working
Would you mind elaborating a bit more on your issue? I'm sure this could be a lot of things. However, I'm sure a more 'universal' fix for this, would be removing and readding your Gmail account to your device.
Go to Settings > Mail, Contacts, Calendars > Tap on the account you're having issues with > Scroll down until you see delete account, and tap on that. > Then just reboot your device, and readd your Gmail account.
This should help you with your issue.