Scrolling performance is a bit low on the main page. I profiled your app using the Open GL device driver in Instruments and your device utilization was capped at 70%, so it isn't a GPU issue (I see you also don't have many blended layers, so that makes sense).

When I profiled with Time Profiler, I notice that 51% of CPU time was spent in backboardd, the UIView/CoreAnimation render server. The only way I know to reduce this is to cut down on number of views, which is typically pretty hard :(

Soundtribe itself was at 38.4%, maybe there's some optimizations to make there?

I'm still on an iPhone 4 so you may be able to ignore this.