I have only found two alternatives to a $1200 Bluetooth headset for connecting the device with MiraCheck to your headset: The PA86A cell phone interface with cables, or the equivalent Bluetooth adapter. Both these plug into your headset cables.
In my case, being a skinflint, I opted for the PA86A as it is only 30% of the Bluetooth adapter cost. The downside is a mess of cables under your feet in the cockpit. This worked OK with my old iPhone 5, which as a 3.5mm audio jack.
However, my new iPhoneX, does not have a 3.5mm audio jack and needs a lightning cable to 3.5mm audio jack to work. My next discovery was that while there are lots of 3.5mm audio jack to lightning adapters on eBay, they are all 3 pole TRS jacks that will not carry the microphone signal. Voice recognition does not work very well without a microphone signal - as I discovered. A 4 pole TRRS adapter is required for a microphone signal.
The only 4 pole TRRS adapter I could find was from Apple. I am pleased to say that my headset microphone did commune with my iPhoneX via the Apple 4 pole adapter.
I must admit that I have not tried the voice recognition function from my headset microphone yet. I wanted it to make phone calls from the air - which I can now do. I cannot see any reason why it would not work with voice recognition on MiraCheck.
One other point: I found Pilot Communications responsive and helpful - despite the negative comments I read on some internet posts.