Skydeck features and pricing depend on the kind of phone that you have.
I have a BlackBerry smartphone
I have an Android phone: a Droid, Droid Eris, Hero, myTouch 3G, G1, CLIQ, Backflip, Devour, Moment, Behold, Incredible, or Nexus One.
Skydeck supports BlackBerry (OS 4.2 or later), iPhone, and Android phones on AT&T, Verizon Wireless, Sprint, and T-Mobile. A limited version of Skydeck is available for most other phones. Skydeck is only available in the US. Msg&Data Rates May Apply.