Coldcard mk5 NFC connection issues

[Polkat]

A video has been released reviewing the Coldcard MK 5 wallet, in which a man tries to connect (export the Xpub) to the Nunchak mobile wallet on various smartphones, but is unable to do so. He claims, however, that his smartphones work perfectly with other NFC devices.
There are just as many complaints on Reddit about poor NFC performance in older Coldcard devices. In my opinion, a wallet that costs nearly $170 shouldn't work like this, and Coldcard needs to test its products more thoroughly.

[SFR10]

A video has been released reviewing the Coldcard MK 5 wallet, in which a man tries to connect (export the Xpub) to the Nunchak mobile wallet on various smartphones, but is unable to do so.

He mentioned "it does register on some phones, but it doesn't work very well ^[35:10]" and he showed it worked with his Galaxy S9.

There are just as many complaints on Reddit about poor NFC performance in older Coldcard devices. In my opinion, a wallet that costs nearly $170 shouldn't work like this, and Coldcard needs to test its products more thoroughly.

You have a point, but after reading "this comment from one of their team members" on Reddit, it appears they've deliberately made it like this on Mk4 ^{[probably as a protection of some sort against threat actors]} and they chose to continue with that approach on Mk5.

[Pmalek]

Ben from BTC Sessions made a video where there is a segment where he compared the new Mk5 with Mk4 and the Q. In that video he says that the NFC tag in the Mk4 isn't working that well. He preferred to use SD cards when dealing with PSBTs on that model. According to him, the NFC feature works much better on the Q. He also said that the same NFC tag used in the Q has been added to the Mk5.

Here is another full review of his on the Mk5 with the correct segment dealing with the Mk5 and Nunchuk: https://youtu.be/KZD6BotYpR4?t=2557&si=fvXLoZcznoT1fdMk

Before using the NFC feature, try going into your settings and disable NFC Push TX. That's what he did. There is a message in the video that you might need several attempts before exporting the keys via NFC. So there are issues with it.

[Polkat]

He mentioned "it does register on some phones, but it doesn't work very well

In this article, Coldcard compares the new differences between the MK4 and MK5 and discusses the improved NFC functionality:

Improved NFC performance, now faster and more reliable (tap in top-right corner).

In my opinion, that’s not entirely true.

Before using the NFC feature, try going into your settings and disable NFC Push TX.

The NFC Push TX feature is designed to instantly broadcast a signed Bitcoin transaction to the network via NFC using a smartphone, and the quality of the connection should not affect the export of the Xpub key in any way.

[Pmalek]

The NFC Push TX feature is designed to instantly broadcast a signed Bitcoin transaction to the network via NFC using a smartphone, and the quality of the connection should not affect the export of the Xpub key in any way.

I understand what you are saying and that the 'NFC Push TX' feature shouldn't be the reason why the NFC connection is bad, but it doesn't hurt to try. In the video I linked to previously, Ben turns it off before exporting his keys from the Mk5 into Nunchuk Wallet. I reckon you can try it as well to see if it improves anything. It doesn't hurt.

[dkbit98]

In my opinion, a wallet that costs nearly $170 shouldn't work like this, and Coldcard needs to test its products more thoroughly.

I seriously doubt NVK lunatic will fix anything with c0ldcard crap, so you just have to wait few years for him to release  c0ldcard mk6  
From all hardware wallet companies only bigger defunct device cemetery from ledger is one with c0dldacrd devices.

In my opinion, that’s not entirely true.

He is a liar.
I would suggest checking out better open source alternatives like Keycard Shell.

[Pmalek]

I would suggest checking out better open source alternatives like Keycard Shell.

Just for the record, does the Keycard Shell support NFC connection? I know it comes with support for QR code signing or you can transfer data via a USB cable if you so choose, but I don't see any mention of NFC. QR codes are better anyways.

This is still a calculator-lookalike device. I remember that you criticized the Coldcard Q for being the ugliest and biggest hardware wallet on the market. If the Q is a Gameboy, the Keycard Shell and the Mk Coldcard models are Gameboy Pockets.

[DaveF]

A video has been released reviewing the Coldcard MK 5 wallet, in which a man tries to connect (export the Xpub) to the Nunchak mobile wallet on various smartphones, but is unable to do so.

He mentioned "it does register on some phones, but it doesn't work very well ^[35:10]" and he showed it worked with his Galaxy S9.

There are just as many complaints on Reddit about poor NFC performance in older Coldcard devices. In my opinion, a wallet that costs nearly $170 shouldn't work like this, and Coldcard needs to test its products more thoroughly.

You have a point, but after reading "this comment from one of their team members" on Reddit, it appears they've deliberately made it like this on Mk4 ^{[probably as a protection of some sort against threat actors]} and they chose to continue with that approach on Mk5.

It's kind of an interesting situation.
I think if you make the NFC signal too weak, you wind up with the issue that the OP and some other people have.
If you push it past a certain point you make it easier for people to read your info. Even if it's not a real risk it's still there.

Although not in the BTC / crypto world I have seen NFC devices that were putting out such a strong signal you can read them from 6 feet away with a Flipper Zero

-Dave

[dkbit98]

Just for the record, does the Keycard Shell support NFC connection?

Keycard Shell does support NFC but only when Keycard is inserted in device, and it uses it for communication with smartphone wallets.
NFC is physically located in the card, and QR codes with camera on Keycard Shell are used for everything else.
This is 100x better and safer than anything c0ldcard have.