UPDATE: Now TV has launched a new service called Now TV Boost that costs an additional £3 a month on top of what you pay for your Now TV passes. Boost enhances your visual and audio experience because it upgrades your video streaming quality from 720p to Full HD (1920x1080) and gives you highly-immersive Dolby Digital 5.1 surround sound. Another useful benefit of choosing Now TV Boost is that it lets you stream content on three devices simultaneously, instead of the default two. Boost also lets you watch two sports channels - Sky Sports Main Event and Sky Sports Premier League - at 50fps, meaning even better video quality.

There are certain caveats to using Now TV Boost, though. First, you'll need an HD TV that supports 1080p resolution, a sound system that supports Dolby Digital 5.1, and a minimum internet speed of at least 12Mbps. While this is below the national average UK broadband speed, you should check your speed first to be sure. All Now TV boxes (except the white box) support Now TV Boost. Similarly, the new service is only available through passes purchased via Now TV, not third-party sellers like iTunes or Vodafone. Now TV Boost is available for all channels offered via the Sky Sports, Cinema, Entertainment and Kids passes, but not the hayu pass.

To get all your Now TV Boost questions answered and purchase Now TV Boost to enhance your experience, head to the What is Now TV Boost? page. This review has been updated to reflect the addition of Now TV Boost to the Now TV Smart Box. Our full review continues below:

Now TV was founded in 2012 and, as a subsidiary to Sky, the brand along with its hardware, such as the Now TV Smart Box, has progressively grown in popularity. It’s designed for those who want to enjoy Sky Sports and Sky’s exclusive TV shows, like Game of Thrones (GoT) and Westworld , without having to commit to expensive, long-term contracts. That's right - if you want to catch up on the latest GoT episodes or want to watch the Premier League without paying for a long-term contract with Sky, your best option is Now TV.

The way it works is simple: you sign up for free, enjoy a short trial and if you want to retain a service, you pay a monthly fee. You can cancel at any time; it’s as straightforward as a contract gets. The catch? Much like Sky’s subscription services, it’s not a one-package to rule them all affair. There are several different “passes” to choose from, covering different content packages.

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Now TV Smart Box 4K review: What you need to know

The company’s latest product is the Smart Box, which now supports up to 4K HDR at 60fps. That’s a massive step up from the Now TV Smart Stick, which only supports up to Full HD. As with the older model, the Smart Box also has a voice search function, which can be activated via the remote control.

Despite the higher resolution, though, you can only watch 4K content via a limited selection of services right now: Netflix and YouTube. There’s no facility to watch live TV in 4K and Sky Sports in 4K is off the menu, too.

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Now TV Smart Box 4K review: Price and competition

The Smart Box is among the cheapest 4K streamers in the UK. It’s available for £46 from Now TV’s website or £50 through Currys PC World , although both options are usually on sale. The extra £4 for the latter includes a month’s free Entertainment, Sky Cinema and Kids TV, plus a day of Sky Sports – we'd spend the extra few quid to get a taster of Now TV's services.

There are a few rival 4K streamers on the market: Roku’s Streaming Stick+ costs around £80 , Amazon’s Fire TV Stick with 4K Ultra HD at £50 and Google’s Chromecast Ultra at £70. There’s also the Apple TV 4K but that’s considerably more expensive at £179.

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Now TV Smart Box 4K review: Setup and ease of use

The Smart Box is elegant enough but it’s not particularly exciting. It’s dressed in glossy black plastic with the Now TV logo stencilled on top in bright pink lettering. The square-shaped box measures 125mm in length and width and is 21mm tall. It's lightweight, too, at only 222g. As for the rest of the design, there’s a small white LED at the front of the device, which remains lit when used and thankfully turns off when the device is in standby.

At the back of the device, is an HDMI 2.0 port, an Ethernet socket, a microSD card slot and a DC power connector, which means the device needs to be powered from the mains. The microSD card slot is there so to provide additional storage for apps. As for wireless connectivity, the Smart Box has dual-band Wi-Fi 802.11ac.

As for audiovisual standards, the Smart Box supports up to 4K HDR at 60fps, though if your TV doesn’t support the higher standard, the Smart Box will automatically adjust to your display’s properties. You can override these settings manually in case the box doesn’t detect your TV correctly.

It’s also worth pointing out that, although you do get HDR10 support, the box doesn’t support Dolby Vision, HLG or HDR10+. On the audio front, there’s Dolby Digital Plus and DTS surround but not Dolby Atmos or DTS:X. It's worth pointing out that it supports both 5.1 and 7.1 pass-through, so if you've got the appropriate sound system or soundbar, you'll get to enjoy your movies and shows in glorious surround sound.

Setting up the Smart Box is straightforward. You’ll need an internet connection, and a mobile phone or computer handy. It took me less than ten minutes to get up and going and the majority of that time I was watching the box receive and install updates. Once you’re set up, the interface is highly intuitive and I was also genuinely impressed by the responsiveness and effective use of voice search. It’s accessed through the remote and accurately picked up actors’ names, film titles and TV shows when I tried it out.

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Now TV Smart Box 4K review: Content

If you’ve ever seen Sky’s TV packages before then Now TV’s offering will look familiar. The company has five different “passes” to choose from: Entertainment, Cinema, Kids, Sky Sports and the reality show service, hayu. Each of these includes some live channels and access to a selection of catch-up content. A comprehensive breakdown of what you get can be found on the Now TV website .

In a nutshell, though, if you want to watch any of Sky’s exclusive content – Sky Sports particularly – Now TV represents the cheapest way of getting access. A monthly subscription is £47 on Sky Q and £34 on Now TV. For Premier League football, a daily or weekly pass might be more economical, depending on how often your team’s matches are broadcast live.

Disappointingly, however, there’s no way of combining packages for a cheaper deal. For example, if you want to watch Keeping up with the Kardashians on the hayu pass and also watch the latest blockbuster films through the Sky Cinema pass, you’ll have to pay £3.99 and £9.99 a month for a total of £13.98.

Regardless of which pass you opt for, though, there’s plenty of content to sink your teeth into. And, even without the passes, you can stream 4K content via Netflix or YouTube, or a from a reasonably broad selection of other apps ( full list here ).

The big catch to the Now TV Smart box is the same as with previous models and that is that Sky-based content, via the Sky Sports, Cinema and Entertainment passes, is still limited in resolution to 720p. Although the company has promised an upgrade to Full HD streaming by the end of the year it has yet to confirm whether it will be charging extra for the service. There’s also no antenna connection, as there was on the old Now TV Smart Box, so you can no longer watch Freeview channels.

The good news is that you can still pause and rewind live TV by up to 30mins and, in third-party apps, you can watch in higher resolution. That’s up to 4K in Netflix and YouTube and Full HD in BBC iPlayer, ITV Hub, All 4 and Demand 5.

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Now TV Smart Box 4K review: Verdict

If you’re looking for a 4K streamer, Now TV’s Smart Box is definitely a decent option. It now, at last, supports Netflix and Prime Video and can deliver that content in 4K, which is great news for those struggling with clunky on-TV apps or having to switch to other streamers to watch their favourite shows. And it still provides a cheaper option for those wanting a cheaper way to watch Sky Sports and Sky’s exclusive TV shows.

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But if you’re not interested in any of Sky’s TV packages, then there are, honestly, better ways to spend your money. The Roku Streaming Stick+, Google Chromecast Ultra and Amazon Fire TV all offer a greater breadth of support for third-party apps and content and, in some cases, have a greater selection of features, too.