That doesn't sound like it would actually be faster though.
I think the best implementation would incorporating something like Google Gesture Search right into the home screen. So you draw the letter L and every app that starts with L would show up. For a while I had nothing on my home screen except the Google Search bar. I'd press search, type in one letter and it would show all apps starting with that letter. That's one step more than I would like though.
What you are describing would be faster if you know the names of all your apps and can recall them when you need them, but what I have in mind would be a way to drill down to what you need for a task, even if you don't recall app names.
It would be a new navigation metaphor for mobile and wouldn't necessarily be faster in all cases, but I think it would be less bland, and I think we're at the point in hardware where an artistic fractal makes some sense as an alternative UI to the equally skeumorphic folder system that is still dominant when you navigate operating systems. It's impossible to get away from heirarchal organization of files, so what I'm describing isn't completely new or different, but it could be an innovative and beautiful interface that doesn't sacrifice functionality. I wish I had the progtammjng skills to do it, but maybe I can work on some mockups of what I mean so perhaps I could bring it to someone to do an app.
I bet there are similar apps or UIs out there already, I just want an OS that looks and behaves that way.