The M series has always stood for mid-range with Sony, usually a vague attempt to pretend a cheaper phone is more premium while secretly nabbing a few features from the mix.
Well, that's actually happened here: a 720p screen, 8GB of storage (of which around 4GB is available), a 13MP Exmor RS rear camera and 2400mAh battery aren't exactly premium specs.
But it does offer a wide angle 5MP camera on the front for improved selfies, and it's water and dust proof too (hence the 'Aqua' part of the name which Sony told us is due to the fact most people don't know its phone are actually waterproof in the middle-tier) – with an exposed USB connector as Sony's managed to work out a way to protect that one too.
Whoa… it's NOT metal?
The big win here goes to the design, as while it's encased in plastic the phone itself looks like it's made of metal – even when viewed rather closely.
Android Lollipop is on board too from the off, with Superior Auto mode even stuck into the front camera for a more feature-rich way to take pictures of oneself.
The notable exceptions here are PS4 Remote Play and some of the more advanced camera features, despite using a 13MP sensor… but for an RRP of €299 (Around £220, $340, AU$435) that's to be expected.
We're still waiting on a Sony Xperia M4 Aqua release date, but it should be before the end of April if previous release cycles are followed.
- All the action from MWC 2015 so far
Get daily insight, inspiration and deals in your inbox
Get the hottest deals available in your inbox plus news, reviews, opinion, analysis and more from the TechRadar team.
Gareth has been part of the consumer technology world in a career spanning three decades. He started life as a staff writer on the fledgling TechRadar, and has grown with the site (primarily as phones, tablets and wearables editor) until becoming Global Editor in Chief in 2018. Gareth has written over 4,000 articles for TechRadar, has contributed expert insight to a number of other publications, chaired panels on zeitgeist technologies, presented at the Gadget Show Live as well as representing the brand on TV and radio for multiple channels including Sky, BBC, ITV and Al-Jazeera. Passionate about fitness, he can bore anyone rigid about stress management, sleep tracking, heart rate variance as well as bemoaning something about the latest iPhone, Galaxy or OLED TV.