Ingress.
Yes, seriously.
Some of you might just shake their heads, but it's fun (and you wouldn't give away as much of your location data on a Jolla, i reckon). On one hand, I've read on a german page that it supposedly runs on the device, on the other hand isn't GPS supposed to be unsupported in Aliendalvik?

Yeah, so, hoping for a native Version (which will never ever happen).