A:AnswerHi, I bought two and I was able to pair both transmitters to a single receiver and it worked; so you can have two people, each one with a different microphone and connect a single receiver to your speaker.
A:AnswerYes it does work. It's just a little complicated to set up.
If you can master getting the device to actually work, then it'll work on your Go PRO 9 because I used it before. But you do Need a Media Mod!!!
A:Answerhey, yes, compatible with any 1/8” stereo minijack.
advice: this is short range use, like interviews, where camera is reasonably near interview or actor.
if body blocks the path to receiver, may have a drop out.
but very cost effective wireless audio if you have controlled scene.
not necessarily choice for long distances.
for instance, interviews, osmo, gimbal, cellphone video, anything within say 20 feet
would be fine option, transmitter on visible side of talent or speaker.
A:AnswerI was able to connect one phone to two of these radios using a lightning-to-3.5mm into the AUX port (not the microphone port) and transmit music over each simultaneously. I was not impressed with the volume, however. But, it was adequate and much better than trying to use Bluetooth, which also has both higher and unpredictable latency and shorter range. These radios work well over much longer distances (up to 100 feet).