20 C a l l f u n c t i o n s■ My ownYou can install applications to your device. To access the applications, select >Applications > My own.Important: Only install and use applications and other software from trustedsources, such as applications that are Symbian Signed or have passed the JavaVerified TM testing.■ Connect a compatible headsetDo not connect products that create anoutput signal as this may cause damage tothe device. Do not connect any voltagesource to the Nokia AV Connector.When connecting any external device or anyheadset, other than those approved by Nokiafor use with this device, to theNokia AV Connector, pay special attention tovolume levels.■ Connect a USB data cableConnect a compatible USB data cableto the USB connector.To select the default USB connectionmode or change the active mode, select> Settings > Connectivity > USB >USB connection mode and the desiredmode. To set whether the default modeis activated automatically, select Ask onconnection > No.3. Call functionsTo adjust the volume during a call, press the volume keys.■ Make a voice call1. In the standby mode, enter the phone number, including the area code. Pressthe clear key to remove a number.