WLAN phones are useful as you can connect to the internet using wireless local area network. With WLAN, you can connect to the internet for free, most of the time (no network charges) unless if you are using network connection.
With WLAN, you can connect more devices to the same access point. If you have many WLAN phones, you can connect all of them to the same access point and surf the internet.
Most of the time restaurants or cafes offer WLAN connection. Therefore, you can use your WLAN phone at these places to connect to the internet for free. Nokia N95 and Nokia N97
are among the most popular WLAN mobile phones in the world.