Normally, your cell phone can only tell you who is calling you if their number is already in your address book. Skydeck Caller ID tells you who is calling you when their number is NOT in your address book.
On Android phones, the Caller ID will appear before the call. On BlackBerries, just let the call ring out and Skydeck will look up the number (Why don’t I get the information before the call?). On the iPhone, Skydeck cannot access your call information to provide Caller ID. Instead, just type the mystery number into the Skydeck application (under ‘Lookup’) and we will tell you who it is.
Skydeck uses multiple databases and verifies the results against the address books of other members who have opted in to this feature. You can easily add the contact to your address book after the call.
Also, If there is no Skydeck application for your phone, subscribe to Skydeck Reverse Lookup instead (What is Reverse Lookup?). Just go to http://skydeck.com on your phone to subscribe to Skydeck Reverse Lookup.