ASUS is a renowned Taiwanese company and one of the largest computing devices manufacturers in the world. They focus primarily on the computer market but, for several years now, they also have been involved in the mobile consumer area. In the last few years, the company has released more than a few smartphones and tablets. The most recent mobile device they created is called ASUS ZenFone 2. It is an elegant smartphone that promises to deliver great performance, a beautifully designed body and plenty of accessories to choose from. Over the last week we were happy to have had the chance to test and play with the ASUS ZenFone 2. Now it's time for us to share with you everything we found about it, in this review:

Hardware Specifications & Packaging

The ASUS ZenFone 2 comes in a colorful box. On its top side you can see pictures of the smartphone, while on its back and sides you'll find details about the smartphone.

The first thing you see when you open the package is the ASUS ZenFone 2.

Inside the box, you'll also find a charger with a detachable USB cable, a set of headphones, the warranty and a quick start guide.

The smartphone is available in multiple colors: you can choose to get it in black, white, red, gray or gold. The ZenFone 2 can also be further customized with one of the special back covers offered by ASUS in their Fusion and Illusion series.

ASUS ZenFone 2 has a beautiful 5.5 inches IPS LCD display, with a Full HD resolution of 1920x1080 pixels and 403 ppi pixel density. When it comes to its processor, the smartphone is available in two different versions: one that runs on an Intel Atom Quad Core Z3580 at 2.3GHz, and one that runs on an Intel Atom Quad Core Z3560 at 1.8GHz. Regardless of the CPU inside, the video is handled by a PowerVR G6430 chip, with support for OpenGL 3.0. If you buy the version with the Z3580 CPU, you will get 4GB of RAM memory, while buying the version with a Z3560 CPU will have "only" 2GB of RAM memory. In terms of storage, ASUS ZenFone 2 is available with 16GB, 32GB or 64GB of internal space. Additionally, you can also use a microSD card, of up to 64GB. This is quite a lot of storage capacity. The autonomy of ASUS ZenFone 2 is handled by a generous 3000mAh lithium-polymer battery.

The ASUS ZenFone 2 we received for testing had the more potent 2.3GHz Intel Z3580 CPU, 4GB of RAM and 32GB of internal storage space.

The rear camera uses a 13 megapixels Toshiba sensor, a dual LED flash, autofocus and HDR capabilities. The front camera has a resolution of 5 megapixels and 85 degrees wide angle lens.

In terms of connectivity options, you get support for microUSB 2.0, Bluetooth 4.0 and wireless networking using the 802.11 a/b/g/n/ac standards, meaning that ASUS ZenFone 2 is able to connect to both 2.4 GHz and 5GHz wireless networks. Also, the smartphone can use two SIM cards at the same time. The first SIM has support for 4G mobile networks, while the secondary supports only 2G.

ASUS ZenFone 2 weighs 170 grams (6 ounces), has a width of 77.2 mm (3 in), a height of 152.5 mm (6 in) and is 10.9 mm (0.43 in) thick.

If you want to get a better look at its detailed specs, open this website: ASUS ZenFone 2 (ZE551ML) Specifications.

The ASUS ZenFone 2 we received for testing came with a few accessories as well: a ZenFone 2 View Flip Cover Deluxe and an ASUS ZenPower rechargeable power bank.

The ZenFone 2 View Flip Cover Deluxe is manufactured from one piece of artificial leather and features a round glass screen on the smartphone's screen. So you can get quick information without opening the cover. With the cover closed, you can switch between up to seven different apps. We must admit that we were impressed by this cover: it feels very high quality. And the design ASUS used for the cover and the apps displayed when the cover is closed is quite special.

If you want to take a better look at what this cover has to offer, open this page: ASUS ZenFone 2 View Flip Cover Deluxe.

The other accessory we got with ASUS ZenFone 2 is an ASUS ZenPower. It's a power bank capable of delivering 10050mAh with up to 2.4A output. The device weighs 215 grams (7.6 ounces) and it's quite small. Its case is made from aluminum and is available in multiple colors: gold, silver, black, blue and magenta. As we've found out, you can use the ASUS ZenPower to charge a ZenFone 2 almost three times before it needs to be recharged itself. Besides being useful, this device made us want to show off with it. It looks and feels like a premium device.

For more information about this power bank, open this website: ASUS ZenPower.

ASUS ZenFone 2 is the best smartphone ever released by ASUS. It's their flagship, and it has lots to offer. Its top version features a 2.3GHz quad-core Intel Atom CPU, 4GB of DDR3 RAM memory and a 13 MP camera. With these impressive specs, the ASUS ZenFone 2 ZE551ML takes its rightful place among the best smartphones on the market.

Design & Build Quality

The ASUS ZenFone 2 has a simple but eye catching design. The body is manufactured from high quality plastic, with brushed surfaces. Every piece of this smartphone tells you that you're looking at a premium device. While it's not the thinnest smartphone out there, the curved back ends with very thin edges of only 3.9 mm (0.15 in).

The top bezel of the ZenFone 2 is dominated by the ASUS logo, sitting right under the ear speaker. The power button is positioned on the top side of the smartphone, which makes it rather hard to get to, as the device itself is pretty large because of its 5.5 inch screen. However, we do understand that the thin edges made it impossible for ASUS to place it on the sides of the device.

ASUS did a very interesting thing when it comes to ZenFone 2's design: the volume rocker is placed right under the rear camera, on the backplate of the smartphone. We must admit that at first we were quite surprised to find these buttons on the back of the ZenFone 2. However, after using them for a while, we found their positioning to be very comfortable. While it's a large smartphone, you can get to the volume rocker even when using the device one handed. Furthermore, having these buttons positioned in the middle area means that it doesn't matter if you're a left or a right handed person - you won't have problems reaching them.

On the bottom bezel of the ZenFone 2, you'll find the three capacitive buttons common on any Android device: Back, Home and Recent Apps.

The back of the ASUS ZenFone 2 looks very nice. Even more, it feels nice. Mainly because its surface is curved and it has a brushed texture. The thin edges enhance this effect further, making the smartphone easy to hold.

As we also mentioned in the previous section of this review, ASUS ZenFone 2 has a 5.5 inch screen. It's an IPS LCD display with Full HD resolution of 1920x1080 pixels and a 403 ppi pixel density. The screen looks great indoors and outdoors. It has a very good contrast ratio, its brightness levels are really high and the colors look sharp and natural. We were very happy to be able to understand what was displayed on the screen, even in direct sunlight.

ASUS ZenFone 2 is a beautifully designed smartphone, that looks and feels great. The body may be large, but the curved back and the thin edges make it feel comfortable, even if we're talking about a smartphone with a 5.5 inch display. Also, the ingenious positioning of the volume rocker right under the rear camera is something we've also seen in the LG G series, and it's a very good example for how a smartphone should be designed from an ergonomic point of view. Up until now, we must say that we like this smartphone a lot.

The Smartphone Experience On ASUS ZenFone 2 ZE551ML

Phone conversations on the ASUS ZenFone 2 are of very good quality. The sound is clear and loud enough to be able to understand the other person with no problems whatsoever. That's true even if you find yourself having a call in a noisy environment. The signal reception is also good: we should mention that we used this smartphone in a geographical area where 4G is available, but the network signal isn't stable.

Another important thing about the ASUS ZenFone 2 is the fact that this is a Dual SIM smartphone. It supports two different SIM cards, that can be active simultaneously. The first SIM supports 4G mobile networks, while the secondary one stops at 2G networks. A high-end smartphone that supports Dual SIM is not something you see everyday. However, many people will find this feature useful.

The audio quality when listening to music or watching movies is also very high. Using the included headphones or keeping it simple and using the loudspeaker, are both good audio experiences. Obviously, using the headphones provides a much better sound fidelity than using the loudspeaker. However, we we also liked how the loudspeaker sounds: it doesn't distort any sounds and it's quite powerful when it comes to its maximum volume.

As for the operating system, ASUS ZenFone 2 uses Android 5.0 Lollipop with ASUS' proprietary ZenUI on top. The ZenUI is a skin developed by ASUS that turns the standard Android experience into a simpler yet beautiful user interface.

The 3000mAh battery is pretty impressive and manages to keep your smartphone running for more than a day. That is, of course, if you don't use it only for playing games, which is something you might be tempted to do, considering the large screen and powerful hardware.

The ASUS ZenFone 2 offers a great smartphone experience. Phone calls are clean and clear regardless of the active SIM card you're using. The signal reception is good. We didn't notice any drops, even if the 4G signal in our geographical region is not that great. The audio quality is also good, both on headphones and when using the loudspeaker.