There are a few of "App Wallets" working on NFC support for both COLDCARD Mk4 and TAPSIGNER/SATSCARD. Like the years we had to push PSBT to be adopted, we expect NFC will take its time too. Not in a hurry. Nunchuk has integrated it well for both COLDCARD and TAPSIGNER/SATSCARD. It's working fairly well with the latest version and they keep on improving it.
Our approach to NFC is simple, almost anything you can do with the MicroSD/USB you can do with the NFC (signing, exporting data, etc...)
Cheers.
Thanks for the information about Nunchuk, I never heard of that one before. I will definitely give it a try, since NFC was the reason to get the MK4 and not the MK3. Honestly I think NFC is not a necessary feature and will probably even scare people away from buying the MK4, but since it is there I want to give it a try.
What I dont really understand is, why you can scrape away the NFC link on the PCB, since it seems like an attacker could easily replace this link if he has physical access to the coldcard.
In any case I like the coldcard so far and use it regularly.
Scraping away the NFC means that if something went horribly wrong with the programming of the coldcard or there was a vulnerability found with NFC it could be disabled without destroying the unit itself. Or if you are just did not want any way for the unit to ever transmit anything.
However, if someone gets physical access to your unit and there is another security issue, if the chip is active or not or even there or not makes little difference.
The ONLY situation that would matter is if they got access to your coldcard, reconnected the NFC and then figured out a way to be near enough to you to get access to the radio waves in a way that they could do something with your funds. At that point see $5 wrench attack, quicker, easier and it just works.....
-Dave