What you see before you is my web-based client for interacting with App.net via any modern browser. It may be just what you're looking for.
I'm writing it mostly to see if I can make a web-based client that does exactly what I want it to do. I think some others of you might like it, too. I'm also just playing with the App.net API to see what new things we can all come up with on it. So, if you have an idea, feel free to throw it my way. No promises, but we'll see what we can all do together.
To try out, just connect with App.net and take it for a spin!
Let me know if you run into any troubles, and we'll get it sorted.