A wireless modem connects to a wireless network instead of to the telephone system. When you connect with a wireless modem, you are attached directly to your wireless ISP (Internet Service Provider) and you can then access the Internet.

Wireless modems operate at speeds comparable to dialup modems, not anywhere near the speed of broadband Internet connections.

Mobile phones can be employed as data modems to form a wireless access point connecting a windows mobile computer to The Internet. The mobile phone is connected via BlueTooth providing a telecommunications gateway between the cellular service provider's data network technology and Point-to-Point Protocol (PPP) spoken by PCs. Almost all current mobile phone models support the Hayes command set, a standard method of controlling modems. The phone appears to be an external modem when connected via serial cable, USB, IrDA infrared or Bluetooth wireless.

The handheld computer needs to send a special telephone number to the phone to get access to the packet data connection. From the PC's viewpoint, the connection still looks like a normal PPP dial-up link, but it is all terminating on the phone, which then handles the exchange of data with the network. Speeds on 2.5G networks are usually in the 30-50kbit/s range.

3G networks have taken this approach to a higher level, using different underlying technology but the same principles. They routinely provide speeds over 300kbit/s.