Does it ask before it does anything?
Always, for anything that costs you money or puts your name somewhere. It rings round shops and prices parts on its own, because that costs you nothing. Buying a part, booking a bay, giving a shop your number, it comes back and asks first, every time.
Does it keep working when I'm not using it?
For the things worth watching, yes. A recall posted against your car, a part you asked it to find coming back in stock, the market moving on a car you said you might sell. It tells you when something changes, and acts on none of it without asking.
How is this different from a chatbot?
A chatbot answers and stops. This one goes and does the next bit: hears the noise, reads the estimate, finds the part, calls the shops, books the appointment. And it knows your car, so you are not starting from scratch every time something rattles.
What phones work?
iPhone XR and newer read the card with nothing installed, hold it to the top with the screen on. Android needs the screen on and unlocked, NFC on, and the card at the middle of the back. Thick metal cases block it; if the tap fails, type the code on the back.
What does $100 get me?
A full year of unlimited Kamochi from the day you activate it, across every car you own. No plans, no per-question charges, no add-ons.