This app was mentioned in 4 comments, with an average of 3.25 upvotes
Pixel Clash RTS might be the closest one you'll get. It has large scale battles, can be played offline, the game is structured for short bursts (even large maps last about 5-8 minutes on average), and has 5 different races you can play as.
For better or worse; the terrain consists of cubes that fall off the map, units caught in the falling cube will be sent to their doom (some units can hover though)...also the game is on portrait mode.
https://play.google.com/store/apps/details?id=digitalbarbarian.rts
https://play.google.com/store/apps/details?id=digitalbarbarian.rts
Pixel Clash RTS is one that comes to mind. The game has 5 completely different Factions, though its more of a Semi-Lane Strategy + Herzog Zwei than full fledged RTS. You don't REALLY take full control of units the way you'd expect in an RTS but that actually makes it friendlier towards low-end phones or ones with the lack of a bigger screen. Each faction actually has a lot of their own strategies that give it a lot of casual depth...oh and the terrain consists of blocks that fall off and your units WILL fall to their death if they even think about crossing it. The game also reinforces plenty of units so expect large scale battles to occur in the span of 5 minutes at worst.
Definitely Pixel Clash RTS from its 5 completely different factions, fast-paced conflict, and short play time (you can finish a full skirmish in less than 5 minutes).
Gameplay video of a full-scale war; notice that its less than 5 minutes long.
Pixel Clash RTS - A simple fast-paced (it has real-time pause) RTS game where you can play as one of 5 different factions. The appeal of this game is the fact that any skirmish becomes a full scale war in less than 5 minutes.
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