App asks for apple Id then crashes

I downloaded ski safari recently (and lili) and ski safari worked fine for a couple of days. Now it doesn't, it asks for an apple id and when I enter it it crashes, if I cancel it it asks again, and if I turn off wifi it crashes. As soon as I installed lili it didn't work and had the same problem. All my other apps are fine though. I've tried a hard reboot, closing out of multitasking bar what do I do to fix this?? I'm going to try a restore from backup so ill let you know how that goes.