Hse Audio Signal Generator and Analyzer for Win 8.1 Phone
(For Windows10 Universal App - Phone - Tablet - PC: look in store for Signal Generator Analyzer.
https://www.microsoft.com/store/apps/9nblggh5g5p4)

- generates single frequencies up to 24 kHz
- sine, square, triangle, ramp, sawtooth, Dirac peaks
- 0.1 Hz steps
- duty-cycle for triangle and square
- 44.1 kHz or 48 kHz
- frequency sweeps
- multi frequency synthesizer with function plotter
- dual channel operation
- white noise, pink noise, brown noise, 1/3oct noise
- background sound under screenlock
- real time FFT spectrum analyzer with peak detection
- 16 bit
- volume, pitch and panning control
- fulfills Nyquist–Shannon sampling theorem
- in trial version up to 1 kHz
- fast signal calculation
- detailed user manual

Usage:
- tune musical instruments
- detect musical notes
- check low frequency room modes
- find resonating things in rooms
- check your phone sound quality
- check devices with test tones
- design and analyze Fourier series
- create Lissajous figures on an oscilloscope
- measure loudspeaker response
- determine distortion in loudspeakers