Auralux, a game developed by Grove Street Games, the same developers that created Grand Theft Auto: The Trilogy -- The Definitive Edition, is a minimalistic and straightforward yet entertaining and enjoyable RTS game anyone can play, even children.
You start with a planet or star of some sort, and each star produces tiny stardust particles around it for protection against other incoming stardust. You can use the stardust to capture uncolonized planets, upgrade the ones you have to produce more stardust, and attack and destroy the enemies' stars. Another remarkable aspect is some nice soothing ambiance in the background, and when two enemy stardusts annihilate each other, they produce melodic music that is equally nice and soothing. Auralux has multiplayer capability, but there do not appear to be enough players to start a match with, or that could be me since I played it on the iPhone. Only the multiplayer needs some improvements.