Sony's first flagship phone of 2018, the Xperia XZ2, is the smartphone it should have made last year.

The Japanese electronics firm has finally unveiled a phone with minimal bezel, a modern 18:9 screen aspect ratio and a refreshed design.

Unfortunately, it is not as well-rounded as it could be, with notable omissions such as not having dual rear cameras and a headphone jack.

The XZ2 will be released on Saturday along a smaller variant, the XZ2 Compact, which has a smaller 5-inch display and body.

Sony has finally given consumers a phone befitting a 2018 flagship, doing away with the bulky, squarish design of its previous flagships. The XZ2 has softer, smoother curves instead of hard lines and edges, giving it a nice, rounded and comfortable feel when held in the hand.

The new design looks and feels great.

The XZ2's IPS LCD display might not be as immediately eye-catching as the Oled display on, say, Samsung's Galaxy S9, but it is nonetheless an impressive display for watching videos or playing games.

The 5.7-inch full HD display is capable of playing high-dynamic range footage with crisp colours and good contrast.

And like most LCD screens, brightness is an issue with the XZ2's screen, which does not go as bright as Oled displays and so will not perform as well under direct sunlight.

One of Sony's strengths has always been its cameras and those on the XZ2 do not disappoint. The phone is capable of taking detailed, crisp and colourful photos, with Sony's default Superior Auto mode being quite good at ascertaining what it is you want to shoot and adjusting the exposure and colour temperature accordingly.

Low-light performance is also very good, with the f/2.0 aperture letting in a good amount of light for not-too-grainy night-time shots.

The XZ2 is now capable of shooting super-slow motion video of up to 960 frames per second in full HD resolution - a step up from the 720p of last year's XZ Premium.

One feature that is sorely lacking is a dual-rear-camera set-up, which means it cannot take "true" portrait shots where the background is blurred out.

While the phone does have a bokeh software that simulates such an effect, it requires you to hold the phone still while it takes two separate photos, which is a bit more inconvenient than on dual-camera phones.

Following Sony's tradition of slipping a few quirky features into each new line of smartphones, the XZ2 comes with a new Dynamic Vibration System, which lets the phone thump and vibrate along to whatever audio is being played on the phone, be it music or videos.

It is a novelty feature and not necessary, but it is still quite fun to turn on for a bit of tactile feedback.

It works better for some videos than others - watching F1 races, for instance, was quite fun, but it added nothing to the experience of watching a rendition of Beethoven's Ninth Symphony by the London Philharmonic Orchestra - although that is subjective.

The phone's latest, speedy Snapdragon 845 processor gives it a smooth performance. However, it still comes with 4GB of RAM when 6GB is gradually becoming the default in flagships. It is more than enough for most users who use the same few apps every day, but those who want to future-proof their phones might prefer an option with more RAM.

The XZ2's standby battery life is excellent, draining at a slow and steady rate when not in active use.

However, moderate everyday use - including connecting to Wi-Fi for texting, to watch videos and play games - will drain it quite quickly, with me usually ending the day with less than 20 per cent battery life.

•Verdict: Sony is making the right moves in its flagship smartphones and the XZ2 finally throws out the Xperia line's blocky, outdated design for a sleeker, modern look. However, it still misses out on core flagship features such as dual cameras.