In Depth: What is MHL and why do you need it?

With MHL you can unchain your media from your phone or tablet and easily display videos, games, photos and more on a big screen.It can be liberating and it's all achievable with the help of just a single cable, yet a lot of people are probably unaware of its existence and many who do know of it still don't really use it.That's a shame, because MHL carries a whole lot of potential, from obvious uses like watching stored videos on a big screen to more inventive applications such as using it in combination with a keyboard and mouse to type documents, essentially turning your smartphone into a desktop computer in the process.To find out more about MHL, its potential uses and its future we spoke to the MHL Consortium, a company founded by Nokia, Samsung, Silicon Image, Sony, and Toshiba, which is responsible for licensing and promoting MHL technology.What is it?The first thing to get out the way is what MHL is and how it works. Essentially one end of an MHL cable will plug into the micro USB port on your phone or tablet while the other will plug into an HDMI port on a television or monitor and your phone's screen will then be mirrored on the external screen.Dr Judy Chen, President of the MHL Consortium, explained that it's a "connectivity solution optimised for outputting a mobile device to a larger display. "Like HDMI it's uncompressed, which is important as that allows it to handle everything in real time, setting it apart from wireless solutions."A MHL Consortium spokesperson added that it can "simultaneously charge the device and it offers the unique ability to control your phone features via the standard TV remote. "MHL-enabled products include smartphones, tablets, Digital TV's, TV accessories, Blu-ray players, audio / video (AV) receivers, monitors, projectors, adapters, automotive accessories, cables, and more."What's it used for?Probably the most obvious use for an MHL cable is to play videos on your phone but view them on a larger screen.That could mean playing locally stored videos or taking advantage of an app such as Netflix, essentially turning your handset into a home media player. Since MHL is simply mirroring the screen of your phone it's compatible with any and all apps.But there are loads of other uses for MHL too. You can use it in combination with a controller for gaming on a big screen and almost replicate a console experience in the process.The MHL Consortium believes that "MHL is a viable substitute for a games console or a set-top box. "When it comes to gaming, an MHL smartphone can be seamlessly paired with a wireless game controller and games can be played with zero lag on the larger screen display."You can use it to view photographs or even connect your smartphone to a Bluetooth keyboard and mouse and turn your phone into a full desktop computer.It comes into its own for all these things even more when travelling, as while you might have a computer, a games console and a media player at home, simply packing an MHL cable and a few optional accessories such as a controller will allow you to bring home entertainment to your hotel room.And that's just the tip of the iceberg. You could also use it while working out, to view exercise apps and videos on a big screen while keeping your phone charged.Or if you have an infotainment system in your car you could interact with your phone through it with the help of MHL and even mirror a satellite navigation app to it.It could even be of use to education or in offices when giving a presentation, as you can connect your smartphone to a projector to show videos, documents and slides, rather than having to bring a laptop in.In fact productivity is a key area of focus for the MHL Consortium. According to Dr Chen "we shouldn't forget about the enterprise aspect."Apple are going after the PC market with a bigger iPad so portable devices encroaching on desktops is something that's already happening. We think MHL is well positioned to capitalise on that."What features does it include?MHL is improving all the time. Versions 1 and 2 support 1080p uncompressed HD video and 8 channel audio and while the MHL Consortium was unwilling to comment on exactly what's next for the technology, the most recent update to MHL 3.0 only came out in August, bringing with it a bunch of new features.These include support for 4K video, enhanced 7.1 surround sound with Dolby TrueHD and DTS-HD Master Audio, support for multiple simultaneous displays and more. It's also backwards compatible with MHL 1 and MHL 2.A spokesperson said "as a set-top box, our latest specification can scale all the way up to 4K so movies will be able to be seen at cinema-quality resolution and supports the latest audio formats such as DTS-HD and Dolby TrueHD. "We also support Remote Control Protocol (RCP) that allows the TV's remote control to access the phone's content and use popular remote buttons such as Stop, Play, Rewind, Pause and Enter. This gives users a real "lean back" experience."While the features of MHL 4.0 remain in the dark, an MHL Consortium spokesperson was able to share some visions the company has for future uses of the technology, saying that there was the potential for "adding MHL inside tomorrow's aeroplanes so passengers can connect their mobile devices to seat backs to watch movies and TV programmes" and "adding MHL to elliptical trainers to charge their phones and give them access to all of their favourite mobile content while they work out."And one thing we can confirm is that MHL won't be going wireless. That's disappointing, as given how many things are now wireless the act of actually having to plug a cable in seems curiously quaint and dated.But there's good reasons for its wired ways, the biggest of which being that according to the MHL Consortium no wireless technology can deliver all of MHL's features in one connection.Then there's the fact that limited speed and bandwidth could lead to quality or latency issues. Dr Chen explained that even for something as simple as scrolling through an Excel spreadsheet it's amazing the difference that MHL makes versus a wireless solution. Not to mention the fact that a wireless connection wouldn't be able to charge your phone and no-one wants their battery to die midway through a rousing speech or five metres from a save point.Getting it out thereOne of the big problems is getting MHL out there, building awareness and getting it into the hands of consumers.A spokesperson for the MHL Consortium told us that "since the retail introduction of the first MHL-enabled devices, the MHL ecosystem has grown to an installed base of more than 400 million products." Which is a great start, but the majority of smartphone users still aren't using it.One reason for that is that while it's now compatible with most Android phones and tablets, MHL is still not compatible with iPhones, iPads, Windows Phone handsets or Windows Tablets. But, as the MHL Consortium explained to us, "MHL is an open standard and connector agnostic, so anything is possible."It is also OS-agnostic as it offers the ability to be implemented in any existing OS platform since most of the features are built-in and therefore plug-and-play."So the support or lack thereof is down to Apple, Microsoft and other relevant manufacturers. As there's so little holding it up there's hope that one day MHL might work on all major smartphones, but that requires Apple and Microsoft to actually want to support the technology.In Apple's case an argument could be made that it's stepping on the toes of the company's expensive proprietary cables which serve a similar purpose and to a lesser extent it may even hinder sales of Apple TV.With that in mind we're not optimistic that Apple will ever embrace it, though there doesn't seem to be as much standing in Microsoft's way.But even when it comes to Android phones and tablets, which do mostly support it, a lot of people aren't taking advantage of MHL.An obvious way to both make people aware of it and get it in their hands would be to include an MHL cable with phones, but that again is down to manufacturers and they have little incentive to do so.Though the MHL Consortium tells us that in certain geographies manufacturers do include the cables with their TV's and monitors, so that's a step in the right direction.For now though if you want a taste of MHL you'll just have to buy a cable for yourself, but with prices starting at only a few pounds there's little reason not to buy one if you have any interest in bringing your smartphone content to a big screen.In most cases the cable is all you need, but there are a whole host of compatible accessories such as controllers and docks to further augment and improve the experience. As for the future of MHL, well that's largely down to the MHL Consortium, but the company has assured us that it's "always thinking of ways to stay ahead of the technology curve to meet the future needs of our technology adopters."It seems there are a wealth of future ways that MHL could be used. While she couldn't comment on specifics, Dr Chen told us that "there are always new things coming up. MHL could be used in cars, fitness equipment, planes or anything else that a phone can be tethered to." So in that sense the sky really is the limit.Sticking with HDMI for your media? Then read up on HDMI 2.0.

Click here to view full content