I'm thinking about making an iphone app for learning/remembering Japanese vocabulary. Basically it would have about 1000 of the most common Japanese words, each with a picture to go with it, and possibly sound of a Japanese speaker speaking the word. It would use a spaced repetition system to help you remember the words.

I'll probably build the app because it's something I think would be useful to myself, but I'm wondering if other people would be interested in it too. Also, if anyone has any ideas to make it better, that would be good too.

My main question is what would differentiate yours from apps that are already out there?
If you're just having 1000 of the most common words, why would someone get that if they could just get the core6k shared anki decks, which is pretty much the same thing, except 6x more. Maybe it's free as opposed to Anki; but you've still got lots of other apps to compete with.
I'm sure it'd be useful for you, but there's many other options to explore when talking about software to help learn vocab.

I didn't know I could get the core 6k on my iPhone with audio, that would be awesome. How do I do that?

Maybe I'll make some sort of game for learning Japanese. I'm just starting to learn iPhone development, and wanted to practice by making something to help my Japanese studies, and hopefully be useful to other Japanese learners too.

My gut tells me that someone else will come in with the details, but...
You can get Anki on iPhone, no problems there.
There's core6k deck in the shared Anki decks.
People have uploaded the audio for it somewhere online...I might even have it stored on my harddrives somewhere...
Hook it all up == yay!

Awesome, I'm actually an iOS developer myself. Well...a variety of mobile devices, but just finished up an iPhone app for a client. Something like this sounds like an excellent project to learn the ropes of it. I want to move into desktop development as well, but can't get the gumption to make the leap.