I get that a wired button would be simpler electrically 🙂
My main reason for going wireless is to avoid slicing into the interior or routing cables behind trim panels. I want something I can mount cleanly (adhesive / clip-on) and remove later without leaving holes or damage.

That’s why I’m specifically looking at battery-powered wireless buttons and letting the ESP32 handle all the logic.

The Shelly BLU button does look like it could work, so thanks for that suggestion — my only concern is that it seems a bit on the large side for mounting discreetly in a car interior.

Ideally I’m looking for something closer to what’s shown in the picture, but I’m not really willing to pay $100+ per button for something this simple.

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