This is a phone app made to compute take-off performance for the Boeing 737-300 aircraft equipped with the 20K engine variant for virtual flying.
!!!NOT FOR REAL LIFE FLIGHTS!!!
It was made by using the procedures and plots described and showed in the Airplane FLight Manual published by Boeing and it applies to the 20K thrust variant described in Appendix 9KS of this manual. Thus it can be applied for virtual flights conducted with the IXEG B737 Classic model, as that is the only B737-300 on the market, and the engine variant matches up.