I had the same question! I'm working on an (early) prototype here.
It's designed for phone and tablets and saves everything directly on your browser. There's a cloud sync feature, but you'll have to send me your Facebook profile to get access. That feature is handy for character entry, since you can type/paste everything on your PC, then sync and have it available on your phone.
I'm actively working on it on weekends, so shoot me an email if you want to help test or even contribute code. I'm focusing on UI and making it table-friendly right now. 4e is on it's way out, so I'm hoping to take a second pass at it to generalize and make it work for other games. I'm also a D&D newbie so I need help from more seasoned players to make it work.