I don't think it was just the Newton that failed, PDAs all had the same problem of no killer feature, Notes, calendars & contacts were never that really compell

I don't think it was just the Newton that failed, PDAs all had the same problem of no killer feature, Notes, calendars & contacts were never that really compelling to most people and even if you had one you might not really use it in practice. Another problem with PDAs was that they often had so poor audio support and no significant storage, so they couldn't be used as a iPod replacement. I've got a iPod Touch now, and the killer feature is the web browser/Email, I don't even have any music or any video stored on it, the web/email is a killer enough feature on it's own. (Music is on my phone, which I always have with me)