The Sony Xperia M4 Aqua looks so similar to the flagship Sony phone - the Xperia Z3 - that it’s almost impossible to tell the difference. And that’s a great thing as both are slim and stylish devices that impress with their looks. Despite having a slightly smaller, 5-inch display( the Z3 features a 5.2-inch screen), the dimensions of the two are actually nearly identical.
Given that the M4 Aqua is sold for half the price of the Xperia Z3, though, one does expect to see some differences, and they are indeed present, but rather than being in the outwards appearance, the difference is in the feel and materials used in the Xperia M4 Aqua. The mid-ranger is an all-plastic affair - with a plastic frame and a reflective plastic back made to resemble glass, while the Xperia Z3 is made of sturdy aluminum and real glass on the back. The M4 Aqua’s plastic build feels a bit cheaper and not as sturdy as the rock solid construction of the Z3, but it is still solidly put together, with no moving parts.
Up front, it’s all about the display and the two front-firing speakers - there are no physical buttons, instead the M4 Aqua relies on on-screen keys for navigation. All the physical keys are on the right: a small, but fairly well defined and easy to find without looking lock/power key, a smallish volume rocker without much of a clicky response below and a two-way camera shutter key further down below.
As its name implies, the Xperia M4 Aqua is protected from the elements - both from dust and water - and it’s officially certified with the IP65/68 rating. That rating guarantees that you can submerge your phone as deep as 5 feet( 1.5 meters) for as long as 30 minutes without it suffering any damage. First, though, make sure that all the protective flaps are closed and keep in mind that you can only submerge it in fresh water as in a swimming pool( and not salty sea/ocean water) .