Hacker News Reader

Not allowed to install, no. Can’t recommend it.

As I said, don’t mind here and there… it’s helpful. But nag me and get replaced.

Its worth mentioning that nobody is doing anybody a favor by using their free software. It seems pretty plain that the free version is a trial you are expected to uninstall or upgrade.

But can I use it to build a better, paid-for, app without having to give up my source code because of the GPL thing?

The Android and iOS versions of stellarium are not open source so you can't compile you're own versions.