Battery
Vivo X21 packs in a non-removable 3,200mAh battery, which seems just about right. Thanks to power efficient Snapdragon 660 processor onboard, I was able to get a decent amount of battery life. In my testing, device easily managed to last an entire day of average usage, which involved playing a bit of PUBG, checking my emails, adding loads of stories on Instagram, and listening to some music on SoundCloud.
Also, when it comes to charging, despite sporting a micro USB port, it does support fast charging. Phone charges from 0 to 100 % in under 110 minutes, which is pretty impressive. While it's not the fastest charger out there, it certainly gets closer to big dogs in market.
In case you rely heavily on your phone are a glued to it then you might need a charging point after 8 to 10 hours. The good part is that the smartphone comes with fast charging support which means that the device can charge up pretty quickly. However, it would have appreciated a lot more with a larger battery.
Camera
Vivo X21's camera setup is similar to what you will find on Vivo V9. It is a dual camera setup consisting of a 12 MP main sensor and 5 MP secondary sensor with f/1.8 and f /2.4 aperture respectively. Camera is a downgrade if you consider megapixel count but it's an upgrade for better low-light photography.
During my initial camera test, results turn out to be convincing. I tested it in day light and it showed promise, however, at times pictures looked artificially enhanced. Phone uses a monochrome lens to click portrait photos, and allows adjustment of blur to strengthen or lighten the effect. It uses AI to separate background from subject in foreground while using portrait mode. Edge detection may not be perfect but it is still pretty good. Camera shot some decent and satisfactory images when I took portrait shots. Bokeh effect is not that great and on many occasions camera blurred both the subject and background. Image quality of images captured in daylight turned out to be really good but they turned out to be grainy and full of noise as soon as light gets dim. Also, Phase detection autofocus is not up to the mark and I often got unstable shots of moving subjects.
Rear camera took good images in decent lighting conditions while surprising me with its HDR mode. HDR mode managed to handle complex scenes with extremely bright and dark areas managing to balance the entire scene. There was some noise and Vivo X21 is no Samsung Galaxy S9 or Google Pixel 2 when it comes to capturing textures, but it was overall good. A positive side to see was that shutter speed and image processing remains snappy on Vivo X21. Unlike other Chinese devices, including some from Vivo, that just makes the images soft for no reason, the Vivo X21 manages to produce great results.
Vivo X21 shoots videos up till 4K at 30 fps, which is fairly decent for a phone at this price point. Camera lacks Optical Image Stabilization and Electronic Image Stabilization so footage comes out pretty shaky, especially in 4K. At 1080p, though, Vivo X21 manages to capture some decent videos with accurate color reproduction and good dynamic range as compared to older Vivo flagships.
Front of Vivo X21 houses a 12MP selfie camera with f/2.0 aperture. Camera app on phone has a very simple user interface. As it is a Vivo phone, it is mandatory that it comes with a beauty mode and with it, you can capture a selfie or a portrait and then beautify it by smoothening skin or removing wrinkles. Camera software does manage to give a range of options to control camera and watermark images. Both the front as well as back camera support portrait mode and HDR modes. Users can also shoot 'Live' images using 'Live Photo' mode.
Overall, it's a decent camera, something you will expect on a midrange smartphone device. While it's not bad, there are plenty of other phones in market with better cameras in this range so Vivo needs to address this issue in their next iteration.
Software
Coming to software, Vivo X21 runs on Android 8.1 Oreo topped with company's own layer of customization via FunTouch OS. Phone has the same User Interface as other Vivo smartphones. Vivo has taken some aspects of iOS such as shape and look of icons, absence of app drawer, quick settings at bottom of screen, etc. I'm personally not a fan of quick settings on Android phones and on Vivo X21, quick settings menu was not easily accessible. Many times I had to swipe three to four times to get hold of menu.
Vivo X21 comes with a gesture mode which allows users to navigate through it with the help of gestures just like on Apple iPhone X. In gesture mode, screen is divided into three parts: Swipe up on right side to open control center, swipe on center to go back to home screen and swipe up on left to go back one screen. If you swipe on central area then screen allows you to scroll through active apps. Status bar is a bit messy as notch covers a lot of area and remaining is not been utilized very well. Notification bar has a very simplistic UI and one has to tap on it to read complete information which can be a turn off for many users.
Launcher is also pretty basic and there is no app drawer which means that all your apps will be placed on multiple home screens. Apart from this, it has all standard features of Android 8.1. With Vivo X21, company is also focusing a lot on the Music and audio experience of smartphone. Device consists of a "Hi-Fi" DAC on board and has a mono speaker located at bottom of device. Audio is satisfactory, though, and nothing great.
It is a software experience which most Vivo users and fans are familiar with and they won't be blown away with anything on Vivo X21's software. For stock Android fans, software on Vivo X21 is a huge no go area.
Conclusion
Vivo X21 is available in market for around $500 dollars or 450 Euros. Phone comes in three colors: Black, Aurora White and Ruby Red. It is an all-rounder with good performance, decent camera and a futuristic new in-display fingerprint scanning technology at heart of device. This phone is a living example to what dedicated Research and Development teams can achieve to beat tech titan like Apple and Samsung.
The biggest concern most people will have is price of this phone. At around 500 dollars, there are plenty of new phones coming out which come with better hardware and camera performance, such as OnePlus 6. Sheer performance, specifications, camera performance and design of OnePlus 6 manages to surpass Vivo X21. If you are a Vivo loyalist or someone who wants to have that in-display fingerprint scanner months before others, then by all means, go ahead and buy this device. However, in case you're looking at more options, there's Samsung Galaxy S8 or Motorola Moto Z2 Force, but they lack the joy of unlocking themselves without a visible fingerprint scanner.
However, Vivo X21 is a fun device that gets a lot of things right. Display is a joy to look at, performance is solid, and fingerprint sensor and facial recognition works well. It looks great, and most of the times, it works just as well as its competitors. It's let down by software, which lacks polish and attention to detail, and comes with several UI elements that just don't make sense. If Vivo can somehow manage to fix that in an update, that would give this phone a great fighting chance against its rivals. In the end, it depends whether you're a Vivo fan or not and whether you want to have futuristic fingerprint scanner quicker than everyone else, and if that's the case, then you won't be disappointed with this phone.