The Xperia Z3+ has been unveiled, and it's coming to succeed the Xperia Z3 as Sony's flagship. It may look similar to its predecessor, but has a whole host of changes on the inside that technically make it the superior phone. But are these updates enough to force your hand and upgrade?

The Xperia Z3 (left) and the Xperia Z3+ (right). Will Sony's latest flagship be a worthwhile upgrade? / © ANDROIDPIT

Xperia Z3+ vs Xperia Z3: release date and price

The Xperia Z3 release date was back in September 2014, while the Xperia Z3+ release date is set for June 2015. That means the two were released within a year of each other, leaving us open to the possibility that there'll be another Xperia release by the end of the year. IFA in September, anyone?

No price has been confirmed yet for the Xperia Z3+, but it's likely to be similar to the Xperia Z3 when it first launched - $649.99 in the US or £549 in the UK (unlocked). These days, you’ll find sellers on Amazon selling the Xperia Z3 for around $500 or £400, but that price is going to plummet when the Xperia Z3+ launches.

Xperia Z3+ vs Xperia Z3: design

The Xperia Z3+ retains the 'omnibalance' design of the Xperia Z3, with only a couple of minor superficial tweaks. The front and back are glass, the sides are aluminum, but the Z3+ is 0.4mm thinner at 6.9mm thanks in part to a smaller battery. The stereo speaker grilles that were above and below the display on the Xperia Z3 are no longer visible on the Xperia Z3+ (though it still features stereo sound).

The stereo speakers on the Xperia Z3+ aren't visible, and the phone is slightly thinner than the Xperia Z3. / © ANDROIDPIT

One crucial change that most people will be happy to see is that the Xperia Z3+ has cut down on all the unsightly waterproof flaps covering the ports on the Xperia Z3. The USB port is uncovered on the Z3+, while the flap covering the microSD and SIM card slots now looks better integrated into the chassis, and looks less, well, flappy.

The right side of the Xperia Z3+ features the volume rocker, power button, and retains the same dedicated camera shutter key we saw on the Xperia Z3, to help with taking photos.

The Xperia Z3 (pictured) features visible speaker grilles above and below the screen, which disappear on the Xperia Z3+. / © ANDROIDPIT

Xperia Z3+ vs Xperia Z3: display

Sony deliberately chose not to offer a QHD screen in the Xperia Z3 to preserve battery life, and it's continuing that philosophy with the Z3+, which has an identical 5.2-inch LCD display with a Full HD (1920 x 1080) resolution. The Gorilla Glass protecting the screen has been bumped up to Gorilla Glass 4, but aside from that it's the exact same screen.

The Xperia Z3+ display (pictured) is exactly the same as that on the Xperia Z3. / © ANDROIDPIT

While some people cry out for QHD on flagship phone displays, questions remain over whether the improved visual fidelity is worth having for less battery. The QHD Samsung Galaxy S6, for instance, doesn't last nearly as long as we'd expect a flagship phone to. With the Xperia Z3+, Sony have followed HTC's philosophy with the One M9 of sticking with what they know works from their previous phone.

Xperia Z3+ vs Xperia Z3: camera

The Z3+ camera continues with the high standards set with the Xperia Z3 - though doesn't build on them. / © Sony

The Xperia Z3 and Z3+ camera are both 20.7 MP models with super-wide 25mm wide-angle lenses, which makes them better at capturing landscapes and general wide shots than other flagships. Onboard are the usual HDR, 'Superior Auto' and 4K video-shooting mods, and we'll need to get some more with the camera to suss out any improvements that were made over the Xperia Z3.

It's not all 'as you were' in the camera department though, as the front-facing camera on the Xperia Z3+ has been bumped up to 5 MP from the Z3's 2.2 MP. It also now uses Sony's Exmor R image sensor, which is better at capturing low-light shots.

Xperia Z3+ vs Xperia Z3: performance

The Xperia Z3 has a quad-core Snapdragon 801, while the Z3+ has an octa-core 64-bit Snapdragon 810 chipset. This technically means that the Xperia Z3+ performance should be on par with that of the HTC One M9, and be much more powerful than the Xperia Z3. This, however, will also depend on how well Sony's UI integrates with Lollipop, and whether it takes advantage of the Snapdragon 810 power onboard. It worked well enough in our short time spent with it, but we'll need to put it through some benchmarking to see whether it matches up to its powerful specs.

Xperia Z3+ vs Xperia Z3: features

The Xperia Z3 shipped with KitKat, but has now for the most part received the much-desired Android Lollipop update. The Xperia Z3+ will come pre-loaded with Lollipop, and adds voice-over LTE (VoLTE) on top of the Z3's Wi-Fi and 4G LTE support.

The Xperia Z3 now features Android Lollipop, so there's no difference between it and the Xperia Z3+ in the software department. / © ANDROIDPIT

Both the Xperia Z3 and Z3+ and water- and dustproof, but the latter goes one better by making its USB charging port waterproof without the need for a flap.

Both phones feature front-facing stereo speakers, though the Xperia Z3+ keeps them invisible. The Xperia Z3+ is set to also include LDAC - Sony's technology that boosts Bluetooth sound quality.

Xperia Z3+ vs Xperia Z3: battery

The Xperia Z3 ships with a 3100 mAh battery that’s good for two days of real-world use. Following the recent flagship trend, the Xperia Z3+ battery is actually marginally smaller than its predecessor's, at 2930mAh. The logic behind this is that the new Snapdragon chipsets - despite being octa-core - are much more power-efficient than older chipsets, allowing for smaller batteries.

You can argue that Sony should've added a bigger battery anyway, so that it lasts much longer than that on the Z3, but Sony prioritized making the Z3+ that little bit slimmer instead, which wouldn't have been possible with a bigger battery.

Xperia Z3+ vs Xperia Z3: early verdict

Of course, our comparison will become more definitive when we do a full review of the Xperia Z3+ in June, but for now we can say that it looks set to have made improvements in several important places, while not spearheading an all-out Xperia revolution.

Is the Z3+ enough of a jump for you to make the switch, or do early signs suggest that you'll stick with your Z3? Let us know in the comments.