After accessing a wallet on Jade, you will see your wallet ID, or your wallet's fingerprint, in the bottom right corner (in this example, B89AB7BC). This alphanumeric string corresponds to a specific wallet, and is useful for recognizing which keys you currently have loaded onto your Jade.
Passphrase or SeedQR users who may access many different wallets should take note of their wallets' 8-character fingerprint and check that the fingerprint matches after logging in with a specific passphrase (for example), to ensure they are interacting with the intended wallet. A recovery phrase with two unique passphrases added to it will lead to different wallet fingerprints, making it useful for checking if you have a typo in your passphrase entry as well.