The Samsung Galaxy S 2 has the capability to output the video to a TV screen, so that you could watch it on the big screen instead on of the tiny mobile screen.
With the Samsung Galaxy S I, you would be able to output video using a 3.5mm cable, however with the newer model, you will need to use the MHL Adapter TV Out HDMI Cable.
If you are using an old TV model, where it does not have HDMI plug, then you could also try the below converter.
1. Plug in the MHL Adapter into the phone.
2. Then connect the other end of the cable into TV HDMI plug.
3. Start to play the movie on your device.
Now when you go on travelling, and while you are stuck at a hotel you can watch movies directly from your galaxy smart phone.
iKross MHL Micro-USB to HDMI Adapter for T-Mobile HTC Sensation 4G, Amaze 4G / Sprint HTC EVO 3D / HTC Flyer / HTC Jetstream / HTC EVO View 4G / Samsung Galaxy S2 S 2 SII S II i9100 i777 / Sprint Samsung Epic 4G Touch D710 / AT&T Samsung Infuse 4G i997 / T-Mobile Samsung Hercules T989 (Free 6FT B/Red HDMI Cable Included)