Do i need to use FFT? Is there any SDK or smth?
Without FFT you can visualize the "scope" of the audio, the actual waveform of the sound. If you want sonogram or something like gfx equalizer does, you'll need to preprocess the audio with FFT. For this there are some SDK support, it's called Accelerator framework. You might want to check out the Apple's aurioTouch2 example.
