Cameras on Xiaomi Mi A1 were great and that is pretty much what you get with Xiaomi Mi A2 as well. Simply put, camera performance of Xiaomi Mi A2 was just as amazing. Phone has a dual camera setup, with one 12 MP sensor and one 20 MP sensor, both having f/1.8 aperture.
While I was a pretty big fan of photos taken by Xiaomi Mi A1, I found that it struggled in low-light, or shooting subjects that tend not to stay still for too long such as kids and animals. Xiaomi obviously thought same, and Xiaomi Mi A2 camera has had a massive overhaul. With a main 12MP snapper, and a 20MP secondary with larger 2 µm pixels which excels in lower light results are excellent. Colors are vibrant but they don't look too artificial as on some previous Xiaomi phones. In auto mode, phone will automatically switch between 12MP and 20MP cameras depending on light condition which prevents shots from blowing out or looking too dark. Portrait mode is aided by an AI mode, enabling what Xiaomi calls 'semantic segmentation'.
All these specs and software tweaks sound good, but most manufacturers are using same Sony sensors, so it's the hardware and software combination that can really help in performance and processing terms. Having used Xiaomi Mi A2 for a short while its first signs are promising: app is quick to load and super-fast to snap away at subjects too. There are a bundle of shooting modes available within the camera too. From more basic, such as Square or Panorama, through to more complex options such as full manual control (which even offers shutter speed control).
In practice, it means that edge detection is greatly improved from previous Xiaomi phones such as Xiaomi Mi 6, which also have a good camera but sometimes produced portraits that looked a little fuzzy around edges. Portraits taken on Xiaomi Mi A2 have sharper edges and even group portraits look great.
At front, Enhanced selfie camera has same 20MP unit that is on the rear, and now comes with a flash for extra help in low light conditions. Even though it's a single camera, portrait selfies look great. Also, Videos shot on this phone also come out great, with phone supporting videos up to 4K at 30 fps with 720p at 120p. Sadly, you don't get to shoot videos up to 60 fps even at 1080p, but overall video quality come out to be pretty good, as they are stabilized with gyro-EIS.
Overall, it's a pretty good camera, even better than I was expecting it to be. At some places, camera performed even as par as Samsung Galaxy S8's camera. Xiaomi fans will be delighted with this and this will be a huge factor which will drive them to buy this phone over its competitors.