Okay, first of, as Mr.Rude has stated, we're not affiliated with RiliSoft. Now your device problems, as you should know an iPod 5 only has 512MB of DDR3 RAM and a dual-core A5 CPU, very much like thee iPhone 4s, so here's some things you can do in hopes of getting thee app to work again.
1) Close down all apps running and reboot your device.
2) Delete any memory (RAM) consuming app and reboot.
3) And if all else fails simply enable your iCloud service and wipe your device clean, though Apple claim to be save, nothing is save just like Sony's PSN getting hacked, so you might have some virus that consumemes both, CPU and memory (RAM).
