Android FFT implementation

We have the need to port to Android an excellent guitar tuner already available in iPhone ("i3f tuner"). itms://[login to view URL] This tuner uses iPhone audio capabilities to sample the guitar string sound, played by the user, and provide the user - as in a traditional analog instrument - a measure of the main string frequency and how far is from the tuning frequency. The user can select the chord he wants to tune, even if automatic chord recognition would be a plus. The iPhone app uses FFT (optimized for the iphone architecture) for signal analysis, and core animation features for the user interface. Anyway the Android app can leverage any existing Android OS framework and we leave the decision to the developer. Besides the developer can use different mechanisms, other than FFT one (e.g.: digital filtering) to achieve the same result. Finally the maximum tolerated sampling time must be 1 second (anyway the faster the better) with a 0.1Hz accuracy. Other than the core section of the application, we need to provide a home page and a "credits" page. All artworks will be provided by us. We can provide the developer the original iPhone source code too. What we need as result is a binary code working on the simulator and on a real device. Besides Android reference OS should be 2.1. The source must be provided too. Also request full support for publishing on Google App Store.