There's a bunch of simple games, as well as some information apps, including AccuWeather. Facebook and Twitter are supported and feeds from these services can be shown side by side with a live TV feed. It's a neat line-up of services and is especially good for video-on-demand content, which is what most people want to access via smart TV apps.
If you're using the set with its desktop stand then you get the benefits of the extra audio system that's built into the stand. This has much meatier speakers than usual and they also fire outwards rather than downwards, so they produce cleaner and clearer audio than most other LED sets that I've used.
It even does a decent job of recreating low-frequency sonic effects in movies. All in all, it makes this a fantastic sounding set. There is a caveat though. If you wall-mount the TV, it switches to the integrated down-firing speakers, which simply don't sound as bassy or as crisp.
2D picture quality
The 55HX853 uses a panel with edge-mounted LEDs that can be dimmed locally to improve black levels. In fact, the first thing that strikes you about this TV is just how well it handles scenes with lots of contrast. It seems to be effortlessly able to handle pictures that have both very bright and very dark areas.
Its control of the backlight dimming is very good for an edge-lit model. There were only a few instances when I spotted blocking, where dark areas positioned next to bright areas aren't as dark as they should be. Backlight consistency was also excellent on my review model, with almost no clouding visible around the edges of the screen -- something that previous Sony LED models have suffered from.
It produces very rich colours with a warm palette, which make movies in particular a pleasure to watch. The deep black levels don't come at the expense of shadow detail either, as even moodier scenes retain lots of subtlety in the darker areas of the image. Detail levels are superb on HD feeds, but it also does an excellent job of upscaling standard-definition images -- something that screens of this size often struggle with.
As with all LED TVs, when motion processing is turned off, the 55HX853's motion handling isn't that impressive. Sony's motion processing technology has always been among the best out there and if you use the Clear or Clear Plus modes, you get very smooth motion without introducing the glassy, video-like effect that cripples similar systems.
There are a couple of negatives though. Firstly, the use of gorilla glass on the front of the screen means that it does tend to reflect ambient light in your room. The TV is no worse than most plasma screens in this regards, but it's worth bearing in mind if you usually have your telly sitting near a window. Secondly, the viewing angles of the panel aren't massively wide, so if you look at the screen from an angle, there's some wash-out on black levels and colour accuracy also drops off slightly.
3D picture quality
When it comes to 3D performance on LED TVs, speed is of the essence. You need a fast panel to avoid crosstalk -- the problem of seeing ghost images on the edges of objects in 3D scenes. The 55HX853 uses a 200Hz panel with backlight blinking that ups the rate to 800Hz. Previous Sony TVs have produced mixed results for 3D, but thankfully 3D images on the 55HX853 are pretty much crosstalk free.
What's more, the sense of depth that this set creates is the best I've seen yet from an LED model. A lot of this seems to be down to Sony's new X-Reality Pro 3D processing engine, which works on 3D images to increase the apparent sharpness, not just of foreground objects, but also background scenery.
Despite the dimming effect of the 3D glasses, pictures remain very bright and colours and contrasts are excellent.
Unfortunately, Sony doesn't ship any glasses with this model, but it currently has a deal running where if you buy one pair of 3D specs for £60, you get a second free, so adding a pair of glasses is relatively cheap by active 3D standards. The TDG-BR250 glasses are quite big and bulky though, especially compared to the latest active specs from Panasonic. Also, the glasses lose the 3D effect if you tilt your head to the side, so you can't lie on a sofa when watching 3D films.
Overall, this is the most convincing TV I've seen from Sony in quite some time. It expertly melds together supreme picture quality for both 2D and 3D material, excellent sound quality and a strong line-up of Internet services. Only the slightly chunky styling and annoying inability to stream common digital formats keep it from achieving a perfect score.