Smartphone companies are now in the habit of releasing flagship devices with incremental upgrades, and no one does it better than Sony.
From its original Xperia Z, which came out at the beginning of 2013, to Z1, Z2, Z3 and the just-released Z3+, each progressive release, which came roughly six months after the one before, has been only a small advancement over the previous model in terms of hardware.
This is the first time that Sony has used the "+" in its model name and the Xperia Z3+ actually has almost the same hardware specifications as the Japan-only Xperia Z4.
In the United States, there is a Xperia Z4v, with slightly different specifications than the Z3+. Then there is a dual SIM version of the Z3+, but only the single SIM model is being sold here.
There is no denying the Xperia Z series of phones has a great design. Its "Omnibalance" design of having two slabs of glass over a rectangle metal frame looks terrific. A similar scheme can be seen in Samsung's latest flagship phone, Galaxy S6.
PROCESSOR: Qualcomm Snapdragon 810 Octa Core 64 bit processor (Quad-core 2.0 GHz + Quad core 1.5 GHz)
DISPLAY: 5.2-inch 1080p Full HD 1,920 x 1,080 pixels (424 ppi), IPS display
CAMERA: (Rear) 1/2.3-inch 20.7 MP Exmor RS, ISO 12,800 (Photo) / 3,200 (Video), 4K video, (Front) 5 MP Exmor R, 25 mm wide angle
OPERATING SYSTEM: Google Android 5.0 Lollipop
MEMORY: 32 GB (microSD expandable up to 128GB), 3 GB RAM
BATTERY: 2,930 mAh (Non-removable)
DESIGN: 1 2 3 4 5
PERFORMANCE: 1 2 3 4 5
VALUE FOR MONEY: 1 2 3 4 5
BATTERY LIFE: 1 2 3 4 5
OVERALL: 1 2 3 4 5
Like its predecessors and siblings, the Z3+ is waterproof. One protective flap seals the plastic SIM card and microSD card tray. The flap has to be locked for the water and dustproof IP68 certification to be effective.
The good news is that the USB port at the base no longer needs to be covered with a cap and is exposed. This makes it easier for the daily charging of the phone.
The plastic SIM card tray, which has been around since the first phone, is still very flimsy though. It looks very out of place against the other premium parts of the phone.
The biggest upgrade is the Snapdragon 810 64-bit processor, which puts the Xperia Z3+ on par with this year's range of flagship devices from other vendors.
Unfortunately, there is still a question of who Sony considers as its rivals. Samsung and Apple use fingerprint sensors on their flagship devices, while LG and Samsung are using higher-resolution quad high- definition displays.
So Sony's new phone is actually behind its peers in terms of new features. Yet, it has priced its phones to match them.
While some may argue that such features are unnecessary, Sony's pricing puts the Xperia Z3+ at a disadvantage. Furthermore, there are China brands that have come up with cheaper devices containing hardware that matches the Z3+.
This phone continues to use the 20.7MP camera of previous Xperia phones. While it produces good image quality, it is now behind most handset makers in terms of features.
For example, most of the new phones include the High Dynamic Range, or HDR, feature. This is where successive shots are taken at different exposures and combined to form one image that incorporates the best lighting conditions of the various shots.
With the Z3+, HDR is an optional feature and only available in manual mode at the 8MP image setting. Furthermore, the camera suffers from a slight shutter lag that makes snapping consecutive shots a frustrating experience.
The good news is that the front camera has been updated to be 5MP, from 2.2MP.
The standout feature remains the waterproof aspect. There is a dedicated shutter button for those who want to snap underwater shots but do not want to have to tap the screen while the device is submerged.
Design-wise, the one thing most users will notice is that unlike the iPhone 6 Plus or Samsung Galaxy S6, the Z3+ camera is flushed with the phone's rear panel and does not protrude out.
Alas, there is no removable battery and Sony has reduced the phone's battery capacity from the Z3's 3,100 mAh to 2,930 mAh.
Despite Sony's claims of the Z3+ having as good a battery performance as the Z3, I found myself needing help from a battery pack to last through the day with this phone.
• Verdict: Fans of Sony's Xperia series will not feel the need to upgrade their current models. If you are looking for a waterproof phone though, this is the best one to get.