I've been adding to OpenStreetMap like a crazy man. In the last few months I've cleaned up and added to my local area and far beyond using my laptop. When I'm on the go, I use apps like Pushpin to add points of interest and gather GPS traces with OSMTrack. As an iPhone user, these are the best OSM options I've found. I want to do more though. What I'd really like to find is an easy, on-the-go way to add addresses on my iPhone. If this exists, please let me know about it.
The android world has Keypad Mapper 3 but there isn't anything similar (that I've found) for iOS. What I'd like to see is something created that can be used while walking down a street that easily lets you record house numbers. It would be ideal if these changes/additions could be immediately added to the OSM database, but I'd even take something like Keypad Mapper 3, that requires you to upload it later.
I'm not an iOS developer. I'm a designer and would love to work with anyone who could make this a reality. If you're a developer and interested in creating something like this, please contact me. I'm sure we could collaborate on something very useful for the OSM community.