The app is designed for use with RAINBOW CAR AUDIO dsp amp SL-PRO-P1250A. This app gives you tools needed to fine tune virtually every aspect of your car audio system. Whether you ara a professional installer or an obsessive audiophile, this app allows you to realize the true potential of DSP tuning tools. Features: 31 bands EQ parametric / grahpic equalization per channel. Phase correction. Crossover type, frequency and slope adjustments. Independent input and output level controls.Time Delay. Input summing and linking. 6 customizable presets.