Signal Path is the most performant spectrum viewing app with beautiful user interface. You can record audio spectrums using microphone and replay them or open large recordings containing I/Q data. Inspect spectrums Spectrums can be selected using two finger drag gesture. Tapping on histogram reveals amplitude value of the selected frequency bin. Adjust thresholds Signal Path automatically expands amplitude threshold range when viewing spectrums. You can also set custom amplitude thresholds if needed. Keeping file size under control Signal Path can set a maximum file size for recording after which file is recreated. Can open wav files and save recorded audio as wav Supported interleaved raw I/Q data formats Float, int8, int16, int32, uInt8, uInt16, and uInt32 Fast Fourier transform lengths 256, 512, 1024, 2048, 4096, 8192 Window functions Rectangular, Blackman, Hamming, and Hann