Android and IOs beep recognizing audio procesing application

The application should start with one on/off button with simple design as possible. The 1st part of program in application should measure values in dB from the captured sound in every 50-100ms (sample rate) . If necesery it should convert the signal from analog to digital (word,byte..) . Then store it into variable “dB-measure”. The 2nd- part : The dB values of the stored(measured) dB variables should be compared to dB pre-set values of the dB pre-set variables”dB-set” and with simple “IF/THEN CONDITION” start/stop to measure time(ms) when the dB are higher/lower than 20dB/0dB and store it into time variable “t-measure”. The 3th part: The program should then compare the measured time values “t-measure” with pre-set values “t-set” and with simple “IF/THEN CONDITION” put the variable “output” 0/1 as writen in 4th part. The 4th part: As “output” turns from 0 to 1 - It should give simple audio signal as output or visual output signal like turning square from green to red. In other words the app should recognize the length of the simple beep signal and give output if the length is false or right