I'm a bit confused by the recent announcement (http://developer.ubuntu.com/2011/09/announcing-the-ubuntu-app-developer-site/) of the new "App" developer site. I've fallen out of Ubuntu development and now only follow news stories to gauge the direction of the OS, and hadn't realized this was coming down the pipe. Perhaps someone from the community could clear this up for me.
I'm very familiar with Ubuntu, Linux, programming, and packaging, but I'm not sure what the conceptual and technical differences are between an Ubuntu app and a Debian package. I've looked a bit into the developer community documentation, but haven't found a straight answer. Can an Ubuntu app be considered a specially configured package that supports Ubuntu's app framework? And how flexible is that? Could I, for example, write an application in Qt and still wrap it in an app?
(As an aside, I'm a little concerned Ubuntu is headed in this direction. I understand that Ubuntu should explore supporting multiple avenues of application development and distribution to stay relevant. But for a engineering user such as myself, this feels like cruft. These remarks are ignorant though. I shouldn't form a solid opinion until I know what's going on.)
Best Answer
An Ubuntu "app" is just an application, just like GIMP, Firefox, or whatever.
They're still Debian packages, we just provide a tool called Quickly that gets people going with PyGTK and make it easy to package and submit to the software center.
You can still write your application in Qt, package it, and submit it to the Software Center, we just are trying to simplify connecting developers like you to make shipping your software to end users easier.