1. A method comprising: establishing a bridged-line group, the bridged-line group including at least one monitoring user associated with a first mobile device having a first mobile device number and at least one secondary user associated with a second mobile device having a second mobile device number; generating a rule for designating the first mobile device number as a primary telephone number associated with the bridged-line group, wherein the rule specifies that the first mobile device number is designated as the primary telephone number associated with the bridged-line group when the first mobile device is located at a pre-determined location; receiving a call intended for the secondary user; determining that the first mobile device number is designated as the primary telephone number associated with the bridged-line group based on the rule and on determining that a geographic location of the first mobile device is within the pre-determined location; routing the call to the monitoring user at the first mobile device number based at least on the determining; and enabling the monitoring user to handle the routed call on the first mobile device.