Thanks for the TWBK recommendation, downloading now.

Since you mentioned Hex-based games, let me recommend my absolute favourite mobile game. It's a very shitty-looking turn based strategy game called Hoplite.

http://toucharcade.com/2014/01/08/hoplite-review/

The gameplay is simple to pick up - you descend into a dungeon, on each level (which fits onto the screen) there are an increasing amount of enemies, and one shrine where you can improve your abilities - throw your spear further, jump more squares, and so on.

Simple as it seems, there's an incredible amount of depth. You can build extremely different characters that require a different approach and tactics. After a few hours playing it feels truly chess-like in how intuitively you find yourself planning moves ahead.

It's got two modes, one is the main "campaign" mode where you can descend to level 26 to "win", or go further for bonus points. The second is a challenge mode with hundred of challenges.

I got it for £2.99 on iPhone and it's given me an embarrassingly large number of hours of enjoyable gameplay. No DLC or in-app purchases, but if this developer ever releases anything again I will be all over it like a powerful blanket.

iPhone
https://itunes.apple.com/gb/app/hoplite/id782438457?mt=8

Android
https://play.google.com/store/apps/details?id=com.magmafortress.hoplite&hl=en 

correction: actually its only level 16 you need to get to to win the standard game 

Hoplite is awesome. This is a fun little writeup of it: https://www.pentadact.com/2014-03-29-the-randomised-tactical-elegance-of-hoplite/

I would also recommend Enyo for a similar thing. The deal with Enyo is that it has a LOT more potential monster/action interactions than Hoplite and the monster behaviors aren't quite as predictable, so you can get annoying surprises sometimes (until you have a lot of experience) and it will never has as much of a perfect clockwork puzzle feel as Hoplite does. Still I like it a lot and it's been my break-it-out-for-a-few-minutes phone game for a long time now.

(I likely have mentioned Hoplite and/or Enyo somewhere back in this thread already, but can't be arsed to check.) 

And downloading Enyo on your recommendation. If you've mentioned hoplite on here there's every chance that was the inspiration for me to get it in the first place!

I'd love to make a game in the Hoplite vein - i'd love to see that combat translated into a more open ended RPG. I know it'd be somewhat like giving chess a story, or making "chess 2: chess quest", but I kind of want it anyway. 

http://surviv.io/ is a 2d battle royale game you play via a web browser. Says it has squad play too.

Warning: the site autoplays music. There's a button in lower right to turn sound off and music volume control near it. 

Neko Atsume - still the best thing ever.

My Oasis - fucking awful pointless tapping game masquerading as some peaceful meditative sim fuck the fucking fuck off.

Mordheim Warband Skirmish - still good for what it is but requires money to heal / resurrect injuries so gave up on my warband.

Monument Valley - still perfect as a mobile game, only started playing it properly recently.

Evo Explores - MV clone, nuff said.

Arcane Quest 3 - Warhammer Quest uber-clone with identical gameplay but full 3D rotatable dungeons. Not had many annoying micro-trans and works well, worth a look.

And now onto something proper....

Titan Quest - I do believe someone recommended me this as it was an early game by Grim Dawn devs. Anyway it's a proper ARPG - paid, thankfully, so you just buy a fucking play a game instead of spending half your time outwitting micro-transactions. It's a bit small on a phone screen (and won't work on my chromebook alas), and has awkward mobile controls, but so far pisses all over 99% of any other mobile bullshit. 

Arcane Quest 3
I think I played a bit of this one, or one of its predecessors. Not quite sold.

Monument Valley
On my to-play list for a loooooong time as well. I'll better try the PC version though.

Titan Quest
Sounds cool, thanks for the tip!

Threw an eye at Neko Atsume, looks dumb AF. Probably gonna try it. 

Seriously. It's hardly a game, but it is ACE.

Trying Monument Valley on PC seems simultaenously a waste of PC's potential, and a waste of a rare good mobile game....IMO.