Wireless Application Protocol (WAP) Question:

No. Not necessarily. If you want to serve up simple WAP content, you can use an existing web server (and just change the MIME types). A mobile will connect to your server through a WAP gateway located in their mobile operator's network.

However, there are some advantages to hosting your applications on a WAP gateway - since it is part of the mobile network. You can have access to information like the mobile's number, identity, and possibly location.