The Google Chromecast has been on sale in the US for a while now and now its reached the UK too. So now you can buy one from your local retailer, Amazon, Currys & PC World, or through Google itself rather than imported through eBay and try it out for yourself. That therefore begs the question, should you bother? Is it worth the hype? And most importantly for some, what is Chromecast?

READ: Chromecast is now available in the UK for £30, BBC iPlayer support included

Chromecast is a streaming dongle, made by Google, that plugs into a television via HDMI. That's its most basic definition, but it's so much more. It offers a wireless gateway to video, music, photos and apps that make your television the centre of the internet.

Chromecast works with apps like Netflix, YouTube and Plex for streaming video but also allows users to open a Chrome tab remotely, on their big screen. This means anything from the internet can be played through the device and onto a telly. But users with smart TVs might say, "I already have that why would I want to pay for it again?" The answer lies in an open ecosystem. Rather than making apps for each different TV, developers can make one that works on any TV via Chromecast.

READ: Google Chromecast review

Chromecast was recently updated by Google to support more video, music and photo formats. It's even rumoured to be bringing 5GHz Wi-Fi and new "TV services". And with an open SDK any developer can take advantage of that platform by adding Chromecast support to their apps using a simple line of code. While smart TVs do get updated, they will never as much support as an open platform that can reach any TV will receive from developers and Google.

Chrome Cast is an add-on for Google's Chrome browser that allows users to fling whatever's on their screen to the TV. It's almost counter-intuitive as TV and mobile platforms embrace apps and this sticks to browser based viewing. Yet it's brilliant too - this doesn’t rely on app updates and uses an already well-developed platform in Chrome.

Smart TVs might have an ever-growing selection of apps, but even with regular updates they're glitchy at best. Big name apps like the BBC iPlayer or Netflix are usually well made, but plenty of others feel rushed to get on a TV and suffer as a result. Chrome Cast, on the other hand, is simply using already establish websites that have been around for years.

From within the Chrome browser the Cast tab can be selected to send whatever is being viewed directly to the TV where Chromecast is plugged in. For YouTube and Netflix there's a specific Cast button which will send the video, making full screen viewing on the TV easy. 

The Cast button mentioned above also features on certain apps allowing users to throw video to the television from a mobile, which then becomes the remote control and the Chromecast device will take the stream from the internet directly.

The current apps supported in the US are Red Bull TV, Netflix, HBO Go, Hulu Plus, Pandora, YouTube, Google Play TV, Movies, and Music, Vevo, Songza, Plex, Post TV, Viki and RealPlayer Cloud.

HBO Go and Hulu Plus don't work in the UK, but the BBC has made a version of iPlayer compatible from launch in the UK to make up for it.

Netflix, YouTube and Google Play's Media apps feature the Cast button function. Knowing Google this will likely appear in more apps with the popularity of Chromecast thanks to its public SDK. It only requires a few lines of code on the part of developers to add in the Cast button to their apps.

Another advantage is that Chromecast actually streams the videos from the internet, rather than from the user's mobile. This means a battery saving where other options, like Apple TV, would put a lot of strain on the mobile streaming the stored video.

As for locally stored files the mighty Plex is there to help. This uses the Wi-Fi router to play movies from your computer on the big screen. It's beautifully made for seamless performance and even blows up nice big images of the films or shows for easy browsing.

READ: Which is the best movie streaming service in the UK? Netflix vs Amazon Prime vs Chromecast and more

Thanks to the Chrome Cast function it's possible to browse web pages on the big screen TV. That said, it will be thrown to the TV and any site hopping will still need to be done from the browser itself. However, it could make for a nice way to show off your photos stored on Dropbox, or read a long article from the couch without holding a device.

The only issue here is the lack of Silverlight support. This is what's needed to play Netflix and Amazon Prime Instant (née Lovefilm). Of course with the Netflix app that's not an issue, but for Amazon Prime Instant users it leaves them out. Presumably this is a move by Google to encourage Amazon to create an app too.

While there are plenty of alternatives out there to make an older television smart, Chromecast is one of the most affordable yet functional. What it lacks in apps now is made up for by its support for browser tab sharing. And the fact it works for both Android and iOS opens up its potential user base even wider.

With a little time, after it is released internationally, it could be the new device developers can't ignore when making apps. Its simplicity of use makes Chromecast a viable upgrade for anyone that enjoys streaming online video, music and photos.

READ: Which is the best movie streaming box for under £100? Apple TV vs Roku vs Now TV and more

Alternatives like the Roku Streaming Stick offer far more apps, with over 800 available right now. But Chromecast is still young where Roku is already a well-established brand. The Roku Stick is also more expensive at $50/£50. Google Chromecast is currently $35 in the US and £30 in the UK.

READ: Roku Streaming Stick vs Google Chromecast: What's the difference?