Display and Speaker Quality
The display on the Xperia Z is definitely something to write home about, where we can enjoy a 5-inch 1080p display with a pixel density of around 441 PPI. 1080p displays on smartphones are really only coming onto the market now, but there are just a few right now, with the Xperia Z obviously being one of them.
The 5-inch 1080p display on the Xperia Z is definitely a sight to behold. It is beautiful, but it does have its downsides, too. The viewing angles on the display were actually quite bad - and while this isn't a point that should make you decide to not buy the phone - we're telling you anyway. There would be times I'd use the Xperia Z laying down in bed, and if I didn't hold it right, the screen looked quite bad with the viewing angle.
Again, not something that makes it a showstopper, but it definitely a point that needs to be addressed by Sony. If they want to provide their devices with a high-end 1080p-capable display, at least make it close to perfect. I'd like to see their next 1080p-capable phone with better viewing angles.
The loud speaker on the Xperia Z was decent, capable of blasting out a surprising amount of audio when watching videos off YouTube, or replaying some movies I recorded on the excellent rear-facing camera. Spotify streaming was also great, again, loud enough for a few people to be sitting around.
Call quality was top notch on the Xperia Z. I had absolutely no complaints about it whatsoever.