Like many of its predecessors, Sony’s new Xperia Z4, which was quietly launched in Japan on Monday, is somewhat disappointing. But a rumored Xperia Z3+ that’s expected to appear in late May could be the real upgrade Sony fans were hoping for.

It’s not that the Xperia Z4 is a bad phone, it’s just that it’s almost exactly like the Xperia Z3 that launched just six months ago. It has the same camera, the same battery, the same amount of RAM; all it really offers is slight design improvements and a newer processor.

Those who already own the Xperia Z3 probably aren’t in a hurry to upgrade, then, but perhaps they’ll be more excited by the rumored Xperia Z3+, which, according to Russian blog Hi-Tech.Mail, will be announced in late May for international markets.

We know very little about the device at this point, but it’s thought it could be based on the leaked Sony smartphone images that were obtained when the company was hacked back in December. They tease 2.5D glass with rounded edges, a “seamless” design, and a new “mono” UI.

It’s likely the device will also feature Qualcomm’s new Snapdragon 810 processor, a bigger battery, and perhaps a bigger (Quad HD?) display, given the name.

We should note, however, that these are simply concept images, so we shouldn’t read too much into them. We probably shouldn’t get too excited about the apparent Xperia Z3+ just yet, either.

• SourceHi-Tech.Mail
• ViaTechnoBuffalo