Okay, but poorly supported
Its an okay app, but it hasnt been updated in years and is full of bugs as a result. I wouldnt give the developer your time or money on this one.
In particular, every system update will make this app re-enable game centre which you then have to disable. It will do this three times in a row for each update. If you dont play it all the time the tutorial will also reset which forces you to waste ten minutes or so.
In all the time Ive had it, its never been updated and this tutorial and game centre nonsense has never been fixed.
Jeremy Bee about
SpellTower, v3.1.3