ASUS made a huge noise back in June during Computex when they announced the 3rd generation Zenfones. With close to half a dozen Zenfone 3 models, the entire product like got a total re-design with better build materials. ASUS also dropped Intel in favor of Qualcomm to power the Zenfone 3.

Ever since ASUS came with with the first Zenfone 3 years ago, they’ve constantly been disrupting a very saturated and competitive smartphone market. And they continue to do so until today with very high ambitions. The Zenfone 3 could solidify their position and penetrate more countries within and outside of Asia.

For the purpose of this review, we’re combining two variants of the Zenfone 3 — the ZE552KL which comes with a 5.5-inch display, 4GB RAM and 64GB storage; and the ZE520KL with a 5.2-inch display, 3GB RAM and 32GB storage.

Check out our unboxing video here first:





We’ve had many encounters with the Zenfone 3 line which started as early as June and then another one early this week with the Zenfone 3 Laser and Zenfone 3 Max so we’ve got a fairly good perspective for this review.

Design and Construction

ASUS made significant changes in the design of the new Zenfone 3. It’s thinner, sleeker and more durable with an all-metal aluminum-grade body. If the previous design and build material of the Zenfone was bland and un-inspiring, the Zenfone 3 has certainly brought its cosmetic makeover to a new level.

Located at the upper right side is the 8-megapixel front camera situated next to the sensors. We can also see here that the bezels are a bit slimmer at 2.1mm compared to its previous iteration and that’s always a good thing. The handset’s 2.5D display which curves outward also makes it seem to minimize the surrounding bezel.

We still have the capacitive buttons below that remains to be unlit so your familiarization with the buttons still plays part when operating the device in the dark. Additionally, there are chrome trimmings surrounding the entire device which add a bit of bling into the handset.

Up top we have the headset jack and microphone, while down at the bottom are the loudspeaker, microphone, and USB Type-C. The corners are curved, reminiscent of the Zenfone Zoom and is made using what appears to be the same high-class material. At the left-hand side we have the compartment for the SIM card and the memory expansion via microSD, while on the right are the metallic keys with concentric circle finish for the power and volume.

At the back, we have the 16-megapixel camera as its main shooter right above the rectangular fingerprint sensor. It is also flanked by the dual LED flash together with the sensor for its tri-tech AF system.

The entire back panel sports the company’s concentric circle design that shows different light accents depending on what angle you look at. What’s interesting here is that the back plate is protected by glass and veers away from the previous plastic material. This is a big step up for the company since it looks and feels more premium.

Measuring 7.7mm thick, it is a lot thinner than the Zenfone 2 which is at 10.9mm. This makes it easier to slide in and out of the pocket. The volume rocker and power/lock buttons are here and no longer at the back and up top as seen on the Zenfone 2.

Overall, the Zenfone 3 sits comfortably on hand thanks to its curved edges. Undoubtedly, it looks more of a flagship device this time around due to the materials used in making the body.

Display and Multimedia

ASUS released two versions of the Zenfone 3 – the ZE552KL with 5.5-inch screen, ZE520KL with 5.2-inch screen. Although varying in screen sizes, the two have Full HD Super IPS+ display mounted with 2.5D Gorilla Glass 3. Pixel density also differs at 401ppi and 424ppi. At that amount, the difference is hard to distinguish.

Screen quality is good as expected of a device of this caliber. Colors are well saturated which can be further tweaked inside settings. You can go for Balanced, Vivid, or Custom. There’s a blue light filter as well to not strain your eyes at night. Viewing angles are great, boasting 178-degrees according to ASUS. At 600 nits, the Zenfone 3 can also churn out enough brightness for outdoor use.

As for its down-firing loudspeakers, it is capable of producing good sound quality with acceptable loudness which will suffice for casual listening. There’s some slight distortion in loud volumes but nothing serious. You can also enhance your sound quality using the AudioWizard app and its built-in presets and equalizer.

OS, UI and Apps

Software is being handled by Android 6.0.1 Marshmallow skinned with ZenUI 3.0. ASUS made few tweaks for the Zenfone 3’s UI like a more vibrant color scheme and rounder icons. Layout is still pretty much the same as the one used in the Zenfone 2 series, so no drastic changes here. On the bright side, you can simply download a good launcher from the Play Store and change its appearance.

We’re expecting ASUS to minimize pre-installed apps with the Zenfone 3. However, after setting up our Google account, we were greeted by a barrage of app updates coming from Google, ASUS, and third-party apps which is annoying.

ASUS also took the liberty to install Facebook, Messenger, Instagram, Amazon Kindle, Puffin, Need for Speed: No Limit, SimCity, Lazada, Beauty Plus, and Trip Advisor. On the bright side, you can uninstall these in case you don’t need them.

Storage-wise, The ZE552KL has 64GB of internal storage with around 52GB left for the user. The ZE520KL model, on the other hand has 32GB of storage with 24GB as usable.

Still very sizable but will fill up eventually especially if you’re planning to load it up with media files. The good thing is it supports microSD cards via SIM 2 slot for up to 128GB.

Camera

What we noticed is that the rear camera is protruding so it doesn’t lay flat on a surface. It’s not a big thing but users that are into details will want to take note of this one.

The hardware itself got some upgrades as well and now features a 16 megapixel sensor with Laser and Phase-Detect AF. There’s also a 4-axis OIS on-board to prevent camera shakes from ruining your photo. Autofocus is fast and locks in quick on a subject even in dim conditions. It’s a bit slow though when shooting in macro so you will need to do some Tap-To-Focus.

Image quality is good with well saturated colors with plenty of details. The 8 megapixel front camera, on the other hand, has a wide-angle lens and good enough for some casual selfies in bright environments. Check out the samples below:

As for in-camera modes, the Zenfone 3 has a ton: Auto, Manual, HDR Pro, Beautification, Super Resolution, Children, Low Light, QR Code, Night, Depth of Field, Effect, Selfie, GIF, Panorama, Selfie Panorama, Miniature, Time, Smart Remove, All Smiles, Slow motion, and Time Lapse. Those like taking photos will surely enjoy these features.

When it comes to video, the Zenfone 3 can shoot 4K resolution clips at 30fps. There’s video stabilization but only limited to 1080p. Watch the sample clips below:

Performance and Benchmarks

This is the first time we’ve encountered the Snapdragon 625 chip. Actually, Qualcomm lists the Zenfone 3 as the only smartphone that is powered by the SD625. The SD625 is composed of 8 cores of ARM Cortex-A53 processors which are 2 clusters of 4 cores with the performance-driven cluster running a max speed of 2.0GHz.

The CPU is then paired with an Adreno 506 graphics processor and 4GB (ZE552KL) or 3GB (ZE520KL) RAM. Performance is good as transitions and animations are smooth. Apps launches fast and shows no signs of chocking or random crashes. The fingerprint scanner is also snappy and registers fingerprint and unlocks the screen in an instant. Gaming (light or graphic intensive like NBA 2K16, Need For Speed: No Limits and Asphalt 8) is a breeze even with the 3GB RAM on the ZE520KL model.

Speaking of RAM, the ZE552KL with 4GB RAM has a total usable memory of 3.5GB with 0.5GB reserved for the system. Without apps running in the background it consumes about 1.4GB, leaving you with 2.1GB free.

The ZE520KL with 3GB RAM, on the other hand, has a total usable memory of 2.8GB with 0.2GB reserved for the system. Thus, leaving you with 1.5GB free.

As for the benchmarks, check out the results below. We’ve put them in a table and included the Zenfone 2 ZE551ML for comparison.

ASUS Zenfone 3 (ZE552KL) ASUS Zenfone 3 (ZE520KL) ASUS Zenfone 2 (ZE551ML) AnTuTu 62,101 61,484 45,029 Quadrant Standard 38,944 40,855 23,660 Vellamo 2,350 (Multicore)

1,586 (Metal)

3,266 (Chrome) 2,361 (Multicore)

1,605 (Metal)

3,283 (Chrome) 1,424 (Multicore)

1,240 (Metal)

3,374 (Chrome) 3D Mark (Sling Shot using ES 3.1) 464 465 PC Mark (Work performance) 6,311 6,379 5,597

As you can see, there’s not much of a difference in benchmark performance between the ZE552KL and ZE520KL, but there’s a notable increase in performance compared to its predecessor, the Zenfone 2 ZE551ML.

Connectivity and Call Quality

We’re also happy to report that the Zenfone 3 supports LTE Band 28 700MHz and Band 3 1800MHz. With support for 2x20MHz carrier aggregation, this is compatible with Smart’s LTE setup for carrier aggregation that they tested last June (see report here with results of up to 222Mbps).

Other basic connectivity features like WiFi, Bluetooth and GPS are present. ASUS made some compromises with the dual-SIM feature though as it now uses a hybrid setup with the SIM 2 slot which serves as the microSD card slot, compared to the previous generation with a dedicated slot. There’s no NFC support for both variants although Asus has stated that the Zenfone 3 Deluxe does have NFC included.

Call quality works as advertised and had no audio issues with the earpiece and mic. Same goes with mobile data as long as you’re in an area with good coverage.

Battery Life

ASUS continues to stick it out with 3,000mAh Li-Po battery with the Zenfone 3 though this time, we think it’s an improvement considering the thinness of the device compared to previous generations. The smaller 5.2-inch variant has a smaller battery capacity at 2,600mAh, a 13% drop from the main variant.

Using PC Mark’s battery bench, the ZE552KL was rated at 13 hours and 46 minutes, while the smaller ZE520KL got 12 hours and 49 minutes which is impressive for a battery below 3,000mAh. This can be attributed to the power-saving features of the Snapdragon 625.

Below is a table of comparison between the two Zenfone 3 models. We’ve also included the older Zenfone 2 ZE551ML to highlight the improvement from its predecessor.

ASUS Zenfone 3 (ZE552KL) ASUS Zenfone 3 (ZE520KL) ASUS Zenfone 2 (ZE551ML) PC Mark 13 hours and 46 minutes 12 hours and 49 minutes 7 hours and 7 minutes Video Loop Test 13 hours and 41 minutes 11 hours and 25 minutes 6 hours and 56 minutes Battery Charging 1 hour, 50 minutes 2 hours, 10 minutes 2 hours, 30 minutes

As for charging times, the ZE552KL can be charged to full in 1 hour and 50 minutes using its own charger while the ZE520KL took 2 hours and 10 minutes. That might seem odd at first considering that the ZE520KL has a smaller 2,600mAh battery. We can only attribute this to the fast charging enabled on the ZE552KL while the ZE520KL does not. We think that Asus only enables fast charging for batteries with 3,000mAh capacity and higher.

Over-all, there’s a huge jump in battery performance for the Zenfone 3 compared to the Zenfone 2. This highlights the optimal battery performance of Qualcomm chips compared to Intel Atom chips.

Conclusion

The Zenfone has definitely matured and this is evident with the new line up of the ASUS Zenfone 3 series. It only took ASUS 3 years from introducing their ground-breaking smartphone line and disrupting the already saturated smartphone market.

The company plans to do it again by offering two variants of the Zenfone 3, giving consumers the flexibility to choose the right product depending on their needs and budget.

The Zenfone 3 (ZE552KL), packing a larger screen, bigger battery and RAM, and double the internal storage, is the beefier of the two. However, it also commands a higher price tag. If that is an issue, this is where the Zenfone 3 (ZE520KL) comes in. Although toned down, most notably in the RAM, storage, and battery departments, it is more affordable, making it accessible to budget-constrained consumers without sacrificing a lot.

That being said, ASUS delivered a one-two combo with the Zenfone 3. Regardless of the model, both have merits that will surely appeal to a wide range of users.





ASUS Zenfone 3 specs:

5.5-inch Full HD Super IPS+ display, 401ppi (ZE552KL)

5.2-inch Full HD Super IPS+ display, 424ppi (ZE520KL)

Corning Gorilla Glass 3, 2.5D

Qualcomm Snapdragon 625 2.0GHz octa-core CPU

8 X ARM Cortex A53

Adreno 506 GPU

4GB RAM, 64GB internal storage (ZE552KL)

3GB RAM, 32GB internal storage (ZE520KL)

up to 128GB via microSD (SIM 2 slot)

16MP rear camera w/ Laser & PDAF AF, 4-axis OIS, dual-LED flash

8MP front camera

4G LTE Cat.6

Dual-SIM

WiFi 802.11 a/b/g/n/ac

Bluetooth 4.2, A2DP

GPS with aGPS, GLONASS

USB Type-C

Fingerprint scanner

3,000mAh battery (ZE552KL)

2,600mAh battery (ZE520KL)

Android 6.0.1 Marshmallow w/ ZenUI 3.0

152.6 x 77.4 x 7.7 mm, 155 g (ZE552KL)

146.9 x 74 x 7.7 mm, 144 g (ZE520KL)

Sapphire Black, Moonlight White, Shimmer Gold

The ASUS Zenfone 3 will be released in the Philippines on August 14 so we don’t have an exact retail price for the Philippines yet. The 5.2-inch Zenfone 3 ZE520KL was provided to us by Widget City. They sell it for Php13,500 (see listing here). The Zenfone 3 5.5 sells for Php16,500 (here).

What we liked about it:

* Much improved in the design

* Premium build

* Great performance

* USB-Type C support

* Good battery life

* 4K Video Recording

What we did not like:

* Still no NFC support

* Lots of bloatware

* Unlit capacitive buttons

Author’s Note: This Zenfone 3 review involves two variants – the ZE552KL and ZE520KL, since both have lots of similar features. Differences between the two like dimensions, display size, internal specs, and benchmarks were highlighted.

Dan Morial and Abe Olandres also contributed to this review.