Thank you!

Regarding Tangem. To keep it short and friendly I'd say we prefer Keycard's open source security model over Tangem's closed one.

Now, Satochip is interesting. Satochip and Keycard both have the NFC + chip combo.

With Shell we now add a camera + QR, which makes any Keycard work with: UniSat, BlueWallet, Sparrow, Backpack, imToken...
Technically, Keycard could be integrated with desktop wallets like Sparrow or Electrum. We just haven't gotten around to doing it, yet.
Of course we warmly invite anyone to contribute Keycard card reader support with Sparrow

For anything EVM, you can use Keycard with Status.im apps (mobile via NFC + desktop via reader)

Good point on interoperabilty! Technically, any JavaCard can work with Shell. I've pinged Satochip to see if they'd like to integrate. Again, our full stack is open to contribution