Description: Most smartphones made within the past few years have the capability to connect to external monitors and/or HDTVs. This is extremely useful if you travel a lot and want to watch movies on something bigger than your smartphone's screen. So how do you know if this feature applies to you?

Some smartphones have the HDMI port on the device itself.

The example below is from a Droid RAZR. It includes your typical microUSB port (left), in addition to a dedicated HDMI port (right). In this case, the HDMI port is a special type known as microHDMI, which needs an adapter to bring it to a full-size HDMI. In general, if a smartphone has a HDMI port built on, it will be in the form of microHDMI.

Droid RAZR has micro USB and HDMI ports

The iPhone needs a proprietary adapter to get to HDMI.

For the iPhone 4 / 4s, you need an adapter to take the 30pin connector out to HDMI (left). The iPhone 5 introduced the lightning connector and also needs a similar adapter (right) to get to HDMI. For video output on the 3G / 3Gs, you only have the option of using an analog video output (yellow RCA or red / green / blue RCA connections).

So what if your phone looks like this?

A Samsung Galaxy S2

The Galaxy S2 only has a microUSB port and nothing else. So how does this connect to an HDTV? Many new smartphones use a technology referred to as MHL (Mobile High-Definition Link).

A Mobile High-Definition Link adapter

In a nutshell, this means you can repurpose the microUSB port to send video to a TV with a compatible MHL adapter. It's as easy as plugging in the adapter to your phone and plugging in a HDMI cable to the other side. These adapters also offer a charging port on the side so you can watch video continuously without the need to recharge. Please note that some of these adapters require your phone charger to operate properly.

I bought a MHL adapter and it didn't work!

If the standard MHL adapter doesn't work for you, then you fall into one of three categories:

1. Your phone is too old and doesn't support MHL.
2. You are the proud owner of a Samsung Galaxy S3 or Galaxy Note 2.
3. You are the proud owner of Google's Nexus 4.

If number 1 refers to you, you can double check your phone's specifications on a website like http://www.phonearena.com to see if your phone truly supports MHL.

If you fall under point number 2, fear not! The standard MHL adapter doesn't work for you, because Samsung customized these phones. Standard MHL uses a 5 pin adapter, whereas Samsung's version is 11 pins. The simple solution is that you need an MHL adapter supplied by Samsung.

If point number 3 applies to you, then your phone doesn't use MHL at all. Google has opted to use a technology called Slimport. The Nexus 4 is the very first smartphone to use Slimport, so the adapters are not too common yet. The adapter looks identical to an MHL adapter, but the difference lies in the technology used to drive the signal. As of this writing (05/2013), the only place to find this adapter for purchase is online.

Once you have the correct adapter, you can use your phone as a powerful media center. Whether it is to play games, watch Netflix, or to write emails on a bigger screen, the possibilities are endless!