There are multiple options to bring TED to your mobile devices.
If you have an iOS device (iPad, iPhone, iPod touch), you can download the official TED app from the app store. This will enable you to view the talks on TED.com either through streaming, or by downloading them to view offline. It also can suggest talks to see based upon the amount of time you have available, and what type of talk you wish to view with the "Inspire Me" feature.
If you use an Android device, you can download the TED app from Google Play. You can stream audio or video of more than 1200 TEDTalks and download for on the go TED!
Another option is to subscribe to the TED podcasts available for free in the iTunes store (link launches iTunes). There you'll find 10 curated collections of TEDTalks, with new talks posted nearly every day.
Nearly all talks are also available for download right on the specific talk's TED.com page. Just look for the download button directly beneath the video player.
You can also subscribe the TED RSS feeds here.