on iOS (tested on iPhone 7 Plus, newest iOS and newest clozemaster version) the text input mode has a bug:
After one submits a cloze word by pressing the blue “ok” button on the keyboard, the keyboard vanishes as it should but the ‘main window’ of the app is somehow not focussed yet (as if the keyboard was still present), so that the green “next” button can not be clicked. Instead, one has to touch the green button a second time until it responds.
Alternatively it is possible to touch the background of the app anywhere first and then touch the green “next” button.
Am I making sense, or do you need more info to reproduce?
I don’t think it should matter, but for completeness:
I was using a Swedish keyboard and I do have the Swedish keyboard active in iOS besides other languages.