Asus Zenfone 3 ZE552KL preview
Battery Life
One advantage of going with the bigger Zenfone 3 ZE552KL is that you get a much larger 3000mAh battery. With an efficient processor and a relatively large battery, we expected the ZenFone 3 to have a good battery life, and it delivered.
The phone consistently provided around 6 hours of screen-on time with two SIM cards and medium use. The phone easily gets through a full day of use and those using it sparingly could even get through two days on a single charge.
Unfortunately, Asus skimped out when it came to providing fast charging support.
The phone ships with a 5V 2A charger, which amounts to an output power of 10W (essentially Qualcomm’s Quick Charge 1.0) and there is no support for a faster charging solution. The fastest we managed to get it to go from 1% to 100% was just under two and a half hours. That's not a lot, but the rate of charging is more suited to overnight charging than a quick top-up when you are in a hurry.
Camera
The image quality from the rear camera is quite good. Images taken in daylight have good amount of detail with a negligible amount of noise. The colors and contrast are ever so slightly bumped up but remain pleasant and close to accurate.
The dynamic range isn't phenomenal, but the HDR mode does help a bit. Unfortunately, there are two HDR modes, and only the one found in the mode selector is the good one, whereas the one that is next to the viewfinder produces blurry, upscaled images with only slightly improved dynamic range.
In low light, the camera does well once again. If things start getting too dim, there are once again two low-light modes to deal with. There's one called Night mode that combines multiple images in an attempt to reduce noise and produces decent results.
Then there is one called just Low Light mode (and the one the camera will suggest when in low light situations), which produces much brighter images even in near pitch darkness but at the cost of resolution (4 megapixels) and for some reason, crops the aspect ratio to 16:9.
The phone can also record up to 4K UHD at 30fps, and the quality is once again quite impressive. The limited dynamic range is evident with videos just like with photos, and there is no HDR mode for video.
Additionally, you can also record in 1080p at up to 60fps, which you can use as it is or slow it down in a video editor to get reasonably high quality 2x slow motion video. There is also a built-in slow motion mode that records in 720p at 120fps.
Display
Since we only have the bigger model with us, our observations are based on this model only.
Regarding image quality, this is one of the better displays we have seen, and one of the best Asus has pushed out. Never mind the 600 nits of brightness, which is almost unbearable indoors and more than perfectly visible outdoors even under direct sunlight. But the display calibration seems to be on point, at least to the naked eye.