To the OP -
There are lots of great Android apps that are useful and others that are just fun. Check on Amazon each day for their free Android app of the day. These are pay for apps that are offered for free for one day only - and there is a new one each day. Many are not worthwhile even free but every so often a really good (and expensive)app is offered.
And Google Play has a lot of good free apps. With a tablet you have plenty of memory and an app is easy to delete if you find you don't like it or don't use it so you can always make room for more. Your Galaxy tablet should have plenty of space for lots of apps. And you can add a micro SD card up to 32 Gb which will store lots of ebooks, movies, and music.