This is pretty good so far. There's no energy, but your hit points don't automatically refill after each match and you can spend coins (earned through play) to refill it between stages or just wait. This isn't too bad of a setup, though, as you get a healing spell during the tutorial that you can use during play.
Some of the lame iap stuff is there, of course, like paying $0.99 to revive if you die in combat (but you still get exp and stuff if you decide to stay dead). There is a 20 day login bonus of a free weapon, but if you don't feel like waiting you can just buy it for $79.99 ( L O L !!! ).
But so far the game seems pretty friendly to free players. None of the iap I've come across seems necessary at all. Who knows if, or what kind of, paywalls will pop up as one gets further in, so we'll just have to see.
As for the game play itself, it's pretty cool. It's a match three, kind of puzzle quest-ish in the spell casting, and nice animations to everything. Liking it so far.