Vivo X21 UD proves that on-screen biometrics does not compromise battery life

Vivo launched the X21 smartphone earlier this year, which came in special version with biometric reader on the screen, called X21 UD . The time has come to check what the advanced intermediary of the Chinese manufacturer has to offer, and whether the always-on-screen biometrics will compromise the device's autonomy.

Vivo reports that the X21 UD has a 3,200 mAh battery to power a large 6.28-inch Super AMOLED screen with Full HD + resolution (1080 x 2280 pixels) and the Snapdragon 660 chipset.

Curiously enough, various battery applications and hardware information in general claim that the model in our hands has 3,900 mAh. 

Anyway, we will conduct our usual battery test in real time to see if Funtouch OS 4.0 with Android 8.1 Oreo will make good use of the 3,200 mAh reported by the manufacturer.

For this, we will follow the standard adopted in all our tests:

• 6 minutes browsing on the All Mobile website using Chrome, videos on YouTube, video on MX Player, streaming on Spotify, offline music on PowerAMP, WhatsApp and games;
• 4 minutes of calls;
• 2 minutes from Facebook, Gmail and Google Maps.

After 16 hours and 51 minutes, the Vivo X21 UD had its battery completely exhausted.

• The smartphone completed a total of 8 hours and 12 minutes with the display turned on during the test.
• We performed 12 complete cycles of tests, which included:
  • 72 minutes browsing in Chrome;
  • 360 minutes of WhatsApp, Spotify, PowerAmp (offline music), MX Player (video) and YouTube (72 minutes each);
  • 72 minutes of games (Pokémon Go, Subway Surfers, Candy Crush, Modern Combat 5, Injustice and Asphalt 8);
  • 72 minutes of Facebook, Gmail and Google Maps (24 minutes each);
  • 48 minutes of voice calls connected to mobile networks;
• The battery presented an average of 34ºC during the test.
• The applications that most consumed the battery were: Injustice, Chrome and Asphalt 8.
• The least consumed was the Telephone.

The Vivo X21 UD has as its differential the biometric reader on the screen, which leaves part of the panel activated all the time waiting for the touch of the user's finger so that the reading is done and the device unlocked.

Even with the technology always active, the battery consumption was very low, making the X21 UD consume practically nothing while it was in standby. The device can stand 16 hours away from the socket with its 3,200 mAh, which was enough to power the 6.28-inch screen and Snapdragon 660 all day long.

The Vivo X21 may not have surprising autonomy, but offers enough performance for the vast majority of users. Not to mention that he was able to keep most of the apps open in RAM during our test (including some games).