A PDA's calendar/agenda data are remotely updatable, preferably in real time. Data changes and or updates are input at a base computer station that includes a pager card with modem and preferably wireless transmission capability. The base computer station transmits data with an appropriate pager ID to a pager system that preferably wirelessly re-broadcasts the data. The PDA receives the re-broadcast data, which preferably is broadcast substantially in real-time. Software stored in and executable by the PDA recognizes the incoming calendar/agenda data and stores the update and new data. Simultaneously, the PDA display flashes an alert to the user that data has just been updated, and the PDA sound transducer can also sound an alert. Preferably the PDA software recognizes any scheduling conflict and, in addition to alerting the user to such conflict, causes the PDA to transmit to the pager service a query concerning the conflict.