Give it a shot. Look at bignoggins advice above. Go for smaller niches instead of trying to be angry birds. There are lots of very useful things that can be done on a phone or tablet. Make something useful that somebody is likely to type into the search on the app store. It can definitely be repeated.

Also, don't worry about there already being an app that does that. There are 600k+ apps. It's been done. But you can find a niche where the best app isn't that great, or at least where you can do it a little better. Make a great app, and make it look great. Don't try submitting things that look terrible. They will get lost in the noise at this point.