I've always wanted a todo list that takes into account concepts from Randy Pausch's Last Lecture. It's roughly this app's time-frame concept, plus a second dimension of important vs not important.
Productivity apps seem to be stuck in the netherworld between super important to society, but also not monetizable enough to warrant the best people to end up working on them.
@staringispolite (Designer of Finish here) good point--there's something interesting about how many people are the list making type, just personality wise. I think this is why Evernote was able to go fairly mainstream--much broader.
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