This app was mentioned in 6 comments, with an average of 1.50 upvotes
Haegemonia
https://play.google.com/store/apps/details?id=com.microids.google.HaegemoniaFull&hl=en_US
Fun story based 4X, too bad it's missing skirmish mode and the solon heritage expansion (it's a port from PC). Looks like they raised the price significantly though.
Imperium Galactica 2? Haegemonia: Legions of Iron?
Haegemonia is still on Google play: https://play.google.com/store/apps/details?id=com.microids.google.HaegemoniaFull&hl=en_US&gl=US
Imperium Galactica 2 is gone - it sounds more like the game you are describing though.