The Vivo X21 introduced the in-display fingerprint sensor and it surely looks cool. The phone’s 6.28-inch notched display has the fingerprint sensor embedded under it. To unlock the phone, all you have to press down on the screen and you’re done. There’s no fingerprint sensor on the outside interrupting the glass design. It’s also curved from the edges for a better grip. There’s a Snapdragon 660 SoC under the hood paired with 6GB of RAM and 128GB of storage.