The Asus ROG Phone stood out last year in the gaming smartphone segment for its pressure-sensitive sensors that act like the shoulder trigger buttons on a game controller.

These AirTriggers changed how users play their mobile games and set the ROG Phone apart from other gaming smartphones that focused on performance and aesthetics. On top of that, Asus created a range of gaming accessories for the ROG Phone, including a dock with a second screen and a detachable game controller.

Asus is sticking to the same formula for the ROG Phone II, available for pre-order at $1,598 from today to Oct 17. The gaming accessories, which are packed in a suitcase, have been revamped and priced at $1,298 (pre-order only) for the entire set.

Design-wise, the ROG Phone II is largely similar to its predecessor. There is no display notch. Instead, dual front-firing speakers that sound loud and powerful, sandwich its 1,080p Oled screen, touted by Asus for its colour accuracy and which offers support for high-dynamic-range videos from Netflix.

The phone has two extra USB-C ports that are used for its gaming accessories. The USB-C port for charging and data transfer is located at the bottom alongside the headphone, but off-centre, as is the headphone jack. This arrangement ensures that the cables do not get in the way while you are gaming when using headphones or charging the phone.

You can also attach the bundled clip-on cooler fan to the middle of the phone to prevent it from overheating. This fan has its own USB-C port for charging and a headphone jack.

Asus has toned down the gaming aesthetics slightly, though the flashy LED-backlit ROG logo and angular circuit lines are still present at the back of the phone. The user interface, too, has a gaming-centric theme that is predominantly black and red. But there is now also a less flashy stock Android theme.

The screen has expanded from 6 inches on the first ROG Phone to 6.59 inches on the sequel. More importantly, the screen's refresh rate has increased from 90Hz to 120Hz, matching the high refresh rate on rivals such as the Razer Phone 2.

This high refresh rate feature ensures that in-game visuals look smooth and feel responsive, especially when moving the camera rapidly. The ROG Phone II is also better able to keep up with your finger as you scroll up and down a Web page and exhibit less smearing of the text and images.

To support this larger, high-refresh-rate screen, which consumes more power, Asus has increased the size of the battery. The ROG Phone II has a 6,000mAh battery, up from 4,000mAh for the previous model.

It means the ROG Phone II can go 1.5 to 2 days on a single charge if I do not play games on it. This drops to a day with heavy gaming or video playback. In our usual video-loop battery test, the ROG Phone II lasted an impressive 14hr25min.

Thanks to the bigger battery, the weight has ballooned from 200g for the ROG Phone to 240g for the new version. The larger size and slippery back also make it rather unwieldy to use with one hand. I almost dropped the phone on a few occasions.

The cameras have been improved. The main 48 megapixel (MP) camera uses the same Sony sensor found in many phones this year. It produces detailed photos that look relatively neutral. The wide-angle camera is useful for landscape shots, though the photos show more noise. Both cameras are quick to focus, but I found it strange for such a fast smartphone that it takes slightly over a second to process the image before it can be viewed in the photo gallery.

The phone also has a long-exposure night mode that takes around five seconds to shoot a photo in low-light conditions. The results are decent enough - objects look brighter, but there is a slight yellowish cast to the photos.

As expected of a gaming smartphone, the ROG Phone II has top-notch hardware. It uses the Qualcomm Snapdragon 855 Plus, a slightly-faster follow-up to the flagship Snapdragon 855 chip. The graphics core of the phone also runs at a higher-than-usual speed. Factor in the 12GB of system memory and fast UFS 3.0 internal storage and the ROG Phone II definitely ranks as one of the fastest Android smartphones available.

I also gave the gaming accessories a short test drive. If you have to choose just one to get, go for the Kunai gamepad ($159), which consists of a holder for the phone and a pair of controllers that attach to the sides of the holder, ala the Nintendo Switch and its Joy-Con controllers.

As for the other accessories, the mobile desktop dock and the WiGig display dock are less useful from a mobile gaming perspective. The Twinview dock, which adds a second screen may be handy for multitasking, but it does not extend the gaming experience to both screens in the games I tried.

Overall, the ROG Phone II has few rivals for mobile gaming. But the improved cameras, huge battery and excellent screen should also appeal to non-gamers looking for a fast and long-lasting smartphone.

FOR

Responsive and vibrant screen

Excellent battery stamina

Dual front-facing speakers

AGAINST

Heavy and unwieldy to use one-handed

Gaming accessories do not come cheap

SPECS

Price: $1,598 (available on Oct 18)

Processor: Qualcomm Snapdragon 855 Plus (Single-core 2.96GHz, triple-core 2.4GHz and quad-core 1.8GHz)

Display: 6.59-inch Amoled, 2,340 x 1,080 pixels, 391 ppi pixel density

Operating system: Android 9.0

Memory: 512GB, 12GB RAM

Rear cameras: 48MP (f/1.8), 13MP ultra-wide (f/2.4, 125-degree)

Front camera: 24MP (f/2.2)

Battery: 6,000mAh

RATING

Features: 4.5/5

Design: 3.5/5

Performance: 5/5

Value for money: 4/5

Battery life: 5/5

Overall: 4/5