You can play movies and videos from your iPhone on your home television. The necessary ingredient is an audio and video (AV) cable. Apple sells two types of cables that support video output from an iPhone to a TV. You also can purchase third-party cables. AV cables connect through the dock connector of an iPhone to either component or composite inputs on a television. Both component and composite connectors are the same RCA-style plugs, but the type of cable you will need depends upon the input supported by your TV
(From http://www.ehow.com/how_7633389_connect-iphone-tv-av-cable.html)
Would it be okay to say "alternative" instead of the "third-party"?
Not to me- third party means made by a different company.