You can't really give a Tangem note to someone else, there's nothing to prove that there isn't another Tangem note that has access to the same private key. Except Tangem promising there isn't, of course.
The chip is highly secure and independently certified. Our proprietary firmware is beautifully simple and audited by Kudelski Group, look it up.
https://twitter.com/kudelski/status/994105585825144832The chip and firmware guarantee no import or export of keys is possible the chip creates it's own unique private key and can never disclose it. There's manufacturer attestation mechanism on the same secure chip to prevent any chance of counterfeits. You don't have to trust anyone.
If I understand this correctly, the chip within the card can be read by a mobile phone and the mobile phone is connected to their APP which links to the Blockchain. So you are not accessing the companies own ledger, with some tokens linked to the card. You have access to the coins that are linked to the Blockchain.
You need a phone with NFC enabled to access the information on the card.
Correct, there's nothing between the chip and the blockchain, no company can control it just an open NFC protocol and our opensource reference apps.