Sony is one of the few Android vendors that mainlines the device drivers for their hardware, so you can reasonably build the newest AOSP version and go to 7.1 if you feel the inclination.

I don't know who is in charge of Sony's smartphone business, but boy did they fucked up. What a confusing mess. Sony used to be a huge brand, innovative and look what happened.

I mean, they had everything; the design chops, the brand power, the tech, the Sony Stores, etc... Everybody knows the iPhone, Sams's Galaxy, LG G series, Moto phones, but Sony really failed to market their Xperia phones properly.

Just for fun, I went to Sony Canada's website to look at their phones and they have 21 models on the page. I'm not joking. https://www.sonymobile.com/ca-fr/products/phones/

I used that phone (the unlocked international w/ fingerprint scanner) for about a year, but the heat problems in the one I had left me helpless/incommunicado in a few inconvenient situations. Eventually preordered a Pixel and haven't looked back.

The only good Android phones I've used (and I've been using Android since the G1) have been ones Google had a hand in: Nexuses, the original Moto X, and the Pixel. The Sony came close, but the heat problems killed it for me.

I would still jump on a well done, small, Android phone.

I have a Z5 Compact as well. Nice little phone, and quite fast. However, I don't think that many developers test their apps on a sub-5" screen, because I've encountered issues with several apps where controls overlap. For example, in VLC's file list the context menu button overlaps with the invisible scroll bar track. It is easy to scroll accidentally. Amazon Music has exactly the same problem, too.

The Android ecosystem is difficult to recommend, and a small Android phone is even more difficult to recommend.

Also have this. Perfect size on this phone, and waterproof. Looks almost new after two years.