Open Moko is a fantastic, super cool idea and the founders are to be lauded, congratulated, and bequeathed many great free beers.
I've been using Linux since 1993 and, though it was a while back, have done a ton (~= 10 yrs) of coding in C and plan on developing some pet apps for OM.
Audio Recorder: I'm guessing that many people (I'm one) would like to have a recorder integrated into their OM phone. MPEG would be the obvious format. Given the many other mentions of video and audio on this site, probably someone else will get to this before I do. For whomever does, here's a few comments I just read today (9/11/2007) from a writers' list:
I'm on the market for a new digital recorder and the pod-favorite olympus dm-10 has been discontinued. any suggestions? thanks, steve * I've got a little Panasonic that I've been pretty happy with, and it came with some easy to use software. It's model number RR-US380, but I'm sure by now there's an update/newer model. * I'm rollin' with the olympus DS-2, love it and mac compatible... (also think its a little less than dm-10) * I have an Olympus WS-310M. It (and it's variants... this one stores 512 MB, but there are other models that store 256 MB and 1 GB) records directly to WMA files. I think those play on Macs, if you have the Mac version of Windows Media Player installed. * Sound is excellent (and in stereo, which sometimes helps), and, even at the highest quality you can fit over 17 hours of recordings on it. * I¹ve got the DS-2 and am not crazy about it. Battery hog, awkward software interface on my mac, and the buttons and folders are fairly complicated. Or maybe I¹m just not very good with it. * I have the Olymous WS-300M and love it. It's very easy to use even for technophobes like me and records up to 8 hours. Works with Macs.
The above would give designers some clues as to what consumers like and don't like and so help design a smooth app. Having a way to record voice audio would, in addition, be a stepping stone to emailing voice messages, having a message answer incoming calls when you can't or don't want to answer, then having voicemail boxes indexed/coded for different callers, and probably several other nice apps.