Introduction
The Vivo X21 UD, released in March 2018, represents an ambitious step forward in Vivo's smartphone lineup, particularly notable for pioneering the under-display fingerprint technology. It aimed to blend cutting-edge features with a sleek design. In this comprehensive review, we dissect the phone's distinct attributes, from its design and display to performance, camera capabilities, and additional features, providing an in-depth analysis of what this phone brings to the table.