How to transform any HDTV into a smart TV

Lots of us jumped on the HD bandwagon the moment HDTVs became available. By being early adopters, we got to enjoy the benefits of HD content from the get-go. Unfortunately, the early equipment needed to watch HDTV was quickly rendered obsolete by better performing, more attractive, and smarter products.
Early HDTVs were strictly high-definition televisions. But modern HDTVs are essentially all-in-one computers that can run apps, access the Web, handle games, and do all sorts of other cool stuff.
If you have an older HDTV without any “smart” features and you can’t afford or just don’t want to upgrade to a newer, more capable set yet, you may be interested in these fairly inexpensive devices for adding smart features to your existing set. 

Cast away

Google’s Chromecast HDMI dongle ($35) is a very affordable way to add some useful capabilities to a TV. It doesn’t add any smart features to an HDTV by itself; but after you install the Chromecast app on an iOS or Android device, you can send content from supported streaming sources—Netflix, Hulu, YouTube, Pandora, Google Play Music & Movies, and a host of others—to an HDTV.  You can also send content from the Google Chrome browser on a Mac or Windows system to a Chromecast device, if you've installed the free Google Cast plug-in.

Google’s affordable Chromecast HDMI dongle enables users to send content from a mobile device or PC running the Google Chrome browser directly to an HDTV.

To set it up, simply plug it into an available HDMI port on your TV and then plug in the Chromecast’s power cable. The power cable uses a standard micro-USB connector, so you may even be able to use the USB port on your TV (if it has one) to feed power to the Chromecast. If not, you can use the included stand-alone power adapter.
Select the correct HDMI input on your TV to see what the Chromecast is displaying onscreen, and run the Chromecast app on your mobile device to complete the setup. The Chromecast will display some identifying information onscreen that you’ll need to enter into the Chromecast app, and the app will scan for the device and let you configure it for your wireless network. When the configuration is complete, you can stream content to your TV by tapping the Chromecast button in a supported app or browser window.

Doin’ it dongle style

On the next level up from simple devices like the Google Chromecast are Android-based HDMI dongles such as the Tronsmart CX-919 and the Measy 'U' line of products (U1A, U2A, and so on). These devices typically sell for about $60 to $100, depending on their specifications (higher-powered devices are more expensive). 

The Tronsmart CX-919 HDMI dongle's innards are similar to those of an Android-based tablet, sans the screen. Connect it to an HDMI input on an HDTV, and it essentially turns the TV into an all-in-one Android-based mini-PC.

These dongles feature internal hardware similar to that of many smartphones and tablets: They have ARM-based SoCs attached to a bit of memory, flash storage, and network controllers, and they run the Android OS. Plug the device in to an available HDMI port on an HDTV and supply the needed power, and the dongle will essentially turn your TV into an all-in-one computer running Android. You’ll have to plug a mouse/keyboard into the dongle (or connect input devices wirelessly via Bluetooth) to complete the setup and click icons or enter text. When you're done, you’ll have access to everything the Web and the Google Play store have to offer.
Other options in this price range include such devices as Apple TV, Roku, and the Boxee Box, which are great products in their own right. They don’t, however, have access to as many apps as the Android-based dongles, which can access virtually anything an Android-based mobile device can.

Going all out

Connecting a Home Theater PC (HTPC) to your HDTV is arguably the most flexible and powerful way to add smart features to your television. With an HTPC, you can run various operating systems and HTPC front ends, and access content available over the Web or via stand-alone applications like Netflix and Hulu. All of that additional flexibility and power requires a larger investment, however, and using an HTPC is usually clunkier and more complex than using a purpose-build dongle or media streaming device.

Home-theater PCs are a great way to bring content and smart features to an HDTV, but they’re the most complex and expensive option.

HTPCs are available in many shapes and sizes, at a wide range of prices. Do-it-yourselfers can configure an HTPC to their liking, but companies like Zotac and ASRock also offer smaller systems designed for use in home-theater environments.
Connecting an HTPC to an HDTV usually involves nothing more than attaching an HDMI cable to an available input on the TV; but array of software, content portals, HTPC front-ends, and player choices available makes it impossible to cover them all. XBMC and Plex are favorites among HTPC enthusiasts, but tons of standalone apps are available too. TechHive's HTPC showdown feature is a must-read.

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