The chill town-building experience Townscaper has finally come to mobile after finding success on PC and console. If you haven't come across gifs or video of it in action, the idea is quite simple. In it, you simply tap around on a body of water to make algorithmically-generated town pieces pop into existence.
Initial taps make a road or walkway pop up, but tapping that roadway makes a house, and then a tower. At any point you can tap elsewhere to begin making new areas to work with, and if they are close enough together they'll pop together and transform into a cohesive whole.