Sony's Xperia Z Ultra represents a great evolution of the original Xperia Z design: it's now waterproof instead of just water-resistant, its 3.5mm headphone jack is no longer hidden behind an annoying plastic flap, and it has an aluminum frame and softer edges. It's also thinner, at 6.5mm versus 7.9mm on the Z, and it has a Triluminos display. The only problem with the Z Ultra? It's not actually a phone, it's a tablet that you can sidetalk with.

The original Xperia Z was already pushing the boundaries of reasonable handset dimensions with its 5-inch screen, but the new 6.4-inch Z Ultra categorically breaks past them and strays into the territory of small tablets. That's not necessarily a bad place to be, as it allows Sony to insert a sizeable 3000mAh battery and provides a big old canvas for stylus input — which the company is pushing in a big way with this new product. You just have to be cognizant of what you're getting yourself into when purchasing an Android slate that makes 5-inch devices look positively compact.

Some of the size reservations with this device can be overcome if you're willing to pair it with a Bluetooth headset. Sony's Smart Bluetooth Handset, also introduced today, aims to fill that role, adding NFC pairing and music player controls, but little else in the way of innovation. Its size is also not exactly discreet, inviting one journalist at Sony's launch event to describe it as "a phone for your phone."

The Xperia Z Ultra is expected to launch in Europe and Asia in September, though Sony's not yet willing to divulge details about any potential US release.