RTA Pro has been calibrated for the microphones of all iPhones and the iPod Touch 5th gen. Custom calibration is also possible. The frequency range is 32Hz to 16kHz. Correction for measuring dB(A) and dB(C) is provided. Apart from 1/3 Octave Bands and Octave Bands, RTA Pro also features the display of a Fast Fourier Transform (FFT). The speed is adjustable to impulse, 128ms and 1 second. The feature list is rounded up by a noise generator with white and pink noise. It is possible to share measurement results via eMail.