As good as PC with some caveats
Controls can be frustrating given the nature of playing on a touchscreen, but overall gameplay is the same and it’s just as fun to play on iPhone/iPad. There are some issues however, either bugs or deliberate decisions, such as diplomacy screens can bug out (scroll will close but not reopen), some A.I settlements never grow in population (majority of settlements were stuck around 500 population when I took them), and there’s no way to cancel automatic unit movements (pressing backspace on PC while they’re moving). Again comparing to the PC experience it’s pretty enjoyable but there are still wrinkles to crease out.