I don't experience any input lag, but I do agree that the keys are very hard to press which is a real bummer. It's better than the onscreen keyboard, but not as great as my previous phone (HP Pre 3) or my mum's phone (BB Passport). Hopefully that will improve once the keys 'sink in' after a while

As for TOHKBD Android apps support: didn't I read that the upcoming system update will allow that?