The addition of sounds for the new Ranger and Paladin classes in Pocket Legends is causing the app to crash on Samsung Galaxy S2 and S3 devices (and possibly other devices). This is a known issue and the Spacetime Studios Development Team is working to resolve it.
As a workaround, if you have access to a desktop computer, you can play on the Chrome or Flash versions of Pocket Legends until the issue is resolved:
Pocket Legends on Chrome.
Pocket Legends on Flash.