I have tried restarting my phone, clearing cache, cleared up alot of room on my phone, and reinstalled. The game still won't open. When it happened I just finished a game then shut down the game. I had some more time to play about 10 or 15 minutes later. Went to open it and it went through the verifying files or somthing page then went to the portrait of the gun bros. Its been stuck not doing anything on the gun bros picture. ive let it stay on that page for about 15 minutes before giveing up on several occasions. Still nothing. My device is a droid DNA.
Our devs are aware of the issue and are working to reproduce it, however, the best course of action is ensure you're running the latest update and to submit a customer service ticket to document your device/OS etc: http://glumobile.custhelp.com/app/ask