The vast majority of RTS games have you building and controlling an army and economy in real time while fighting against the opposing side. You usually have multiple things going on at once and must focus attention on several ongoing tasks. As many experienced players know, it can get hectic at times.
Battles can be won or lost in a split second over slightest details, so controls and responsiveness are key. Quantum Collapse is doing a great job so far. The game is fully controlled by touch, and everything feels natural, from the two-finger scrolling and zooming.
Tapping a fighting unit will select all units of the same type that are close by, allowing easy movement of troops. Double tapping a unit allows the player to single it out from the pack. These simple controls should be easy for beginners to learn and will give experts the freedom needed to quickly yet precisely plan their moves.