Demise of Nations is a well made little Civ-like (with simple city management) or Total-War-Rome-like (but only on the campaign map) that I've just started playing a bit of. Hex based, and synchronous turn based, but with a nice mix of units and rock-scissor-paper-catapult to play around with (various units have many different match-up bonuses), a quasi-historical setting in the base game for free (most of ancient Europe/North Africa/Western Asia is the base map with plenty of civs to try out, but modern/future Europe is available as a freebie d/l as well), it has online multi-player, and even a mod-making and map design kit available for the paid version. Seems to have modern, future, WWII, and full earth scenarios available at least, so the system is versatile enough to do a bit.
Kind of a simple yet complex war game, that I'm really liking the vibe of. OK'ish diplomacy system, plenty of win conditions available for victory (conquest, domination, regicide, etc), strategic resources and map control, and even a weather system for those horrible Russian-esque "don't go there in winter, you'll lose" things happening. Seems really well rounded, and I recommend anyone that wants a bit more wargame than most civ-lites can offer, or that always wanted to roll on through as the barbaric Gaulish Brutes in TW:R (but that mostly liked the turn-based-strategy side of TW), to give it a go. Even has a basic tutorial, so you can learn what the thingies do, but it's all pretty simple. Available on Android, iOS and PC, with multiplatform online play in the free version, so it might be fun to get a group game going some day. Even teams Vs AI is available, until we know what we're doing properly.
Total War: Rome: "the turn based version", on your mobile for free, is worth checking out.
(digging the fact that each civ has its own separate unit list, with proper ('ish) names and everything. Separate Roman troop types, although it's odd that you have an "army" of skirmishers or legionnaires. Still better than anything Civ has done for that era, and way more like TW in that regard. Heaps of generic stuff still (Brutes everywhere!) , but at least they slightly themed some civs. Which is a good thing
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(wow. "Germanic" civs, ie: everyone properly north of the Mediterranean Sea, gets a "Pagan Priest" unit. That can make it rain or snow within three tiles to give you those horrible Russian winters. Nice. Strategic magic is in, even in a semi-historical setting
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(#3? I guess. This looks fairly moddable. For nukes and stuff. I think it might not be too hard to whip some stuff up. GoT or Ultima IV minus 1/2 (the Rise of Britannia) is what I'm thinking though. Just for a laugh.)