@chasmayhear You may want to post this under one of the tinnitus discussions to make it easier for others to find.
I've not heard of a tinnitus that could be heard by others but it is conceivable. Tinnitus originates in the brain so I suppose that there could be brain matter that could act as a speaker diaphragm??? And if someone could hear that without a stethoscope, they would probably be driven to insanity. The signal would be weak. I sometimes wish I had super hearing but it's probably a blessing to have what I do have.
Spectroid must be an Android app since I cannot find it for my iPhone. I do see Spectrum but it is actually called Audio Spectrum Analyzer dB RTA and has good reviews. When you put your thumb over the microphone, it's probably picking up your heart rate. Nice that a smartphone has so many uses!
Tony in Michigan