Mobilizing applications

Wireless communication links are expensive and slow, and are therefore a scarce resource. Their usage should be subject to special scrutiny, especially when used by general-purpose application programs. We present the services of the "Mobile Application Framework" which supports conventional applications while using these links in three aspects: first, by optimizing outgoing communication calls via call interception and the spoofing of replies; second, by allowing disconnected operation through file logging and automatic modification reconciliation; and third, by scheduling and communication calls to allow the user to specify a monetary communications budget. As an example application, we show how the system can be used to mobilize a conventional e-mail system. Similar functionality to that provided by dedicated mobile e-mail clients and the ability to adapt to changing network environments is achieved without requiring any changes to the e-mail system itself or its user interface.