It’s not as much about the phone you’re using as the equipment the call originates from and is routed through: http://en.wikipedia.org/wiki/Caller_ID#Calling-line_identification:
Caller ID is made up of two separate pieces of information: the calling number and the billing (or subscriber) name where available. When an originating phone switch sends out a phone number as caller ID, the telephone company receiving the call is responsible for looking up the name of the subscriber in a database. It is for this reason that mobile phone callers appear as WIRELESS CALLER, or the location where the phone number is registered (these vary based on which company owns the block of numbers, not the provider to which a number may have been ported). Additionally, nothing ensures that the number sent by a switch is the actual number where the call originated; telephone switch initiating the call may send any digit string desired as caller ID. As such, the telephone switch and, therefore, the operating entity must also be trusted to provide secure authentication.
The displayed caller ID also depends on the equipment originating the call.
If the call originates on a POTS line (a standard loop start line) caller ID is provided by the service provider’s local switch. Since the network does not connect the caller to the callee until the phone is answered generally the caller ID signal cannot be altered by the caller. Most service providers however, allow the caller to block caller ID presentation through the vertical service code *62.
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I use the Google Voice service. One thing it illustrates clearly is that Caller ID, just like email message headers, is completely and totally unreliable as a trustworthy identification.
Just like anyone can manipulate email headers to make the “From:” field look like the spam you just received was sent from your best friend, Google Voice can be configured to show you the Caller ID that you choose: either your Google Voice phone number (so you know which “line” the call is coming in on) or the caller’s own caller id (so you know who’s ringing you). If Google wanted to, they could simply make the caller id show as “Mickey Mouse”. And with the right equipment, so can anyone else.