Bluetooth Mics
I'm seeking recommendations for a decent Bluetooth mics that is directional to connect to an iPhone. If it has a switch or button to start/stop recordings, all the better. Main use will be bird sounds. Thanks.
iPhone 8 Plus
"I don't plan to make videos so I take it I can skip over the video mics?"
Not necessarily, a video mic might be beneficial if it had a narrow pickup pattern. I suggested a "shotgun" type mic because they have a narrower pickup field which is what you would probably want if you are trying to record bird sounds. With a narrower pickup pattern, it will pickup more sound in the direction that the mic is pointing and less of the surrounding ambient noises.
Also do a search for boom mics which are also considered shotgun type mics. They use boom mics when recording people talking in movies. it's a very narrow field so it mostly picks up just the vocals and not the surrounding noises.
What type of mic is a boom mic?
A boom mic is, by definition, any mic at the end of a boom pole. Shotgun microphones are highly directional mics with hyper or supercardioid capsules and interference tubes. Boom mics are typically shotgun mics, but shotgun mics are used in more applications than just boom miking.
Here are some articles about pickup patterns of microphones, it might help you chose which one you want.
Shotgun mic patterns
Boom mic patterns