Heh, I'm gonna be a smart ass and say the keyboard that's built into the phone... one of the main reasons I wanted the TP2
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But for soft kbd's, SwiftKey wasn't bad... but I got sick of the autocomplete all the time - not sure if you can restrict it to only the soft kbd or what, but it was always taking over. It did get pretty good over time, but I still found it obnoxious as I'm usually on the full qwerty, in which case I'm usually spelling out the whole word anyways
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