We don't currently have a sane way to deal with input with the stock QPA, so, you'll probably want to go custom Qt if Qt is what you want.
Or custom all the things and do everything by hand, with FBInk's help, which is also a possibility, depending on how much UI you actually need.
@shermp also had some success by going with a <insert favorite language here> backend + web frontend approach using the stock beta browser (which, fair warning, is an old, old, old, and heavily limited WebKit version).
TL;DR: Not NickelTC after all
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