I got really into chip defense. The concept is a really fun twist on classic enemy hp mechanisms in tower defense. However I think the game's controls design "scales" poorly with its difficulty curve. Building a new "tower" takes too many taps for the game to continue running in the background. Same for upgrading towers. The worst is when starting a level, you kind of need to rush placing towers to not mechanically end up in a fail state.

If the game let you build and upgrade when paused (or at least queue up those actions to be executed when un-paused) I would have continued playing it.