Use Cases for Push Functionality

Many types of apps can benefit from push functionality. For example, games that require users to take turns, such as chess, could be written using push. Because one turn can take a long time, when one player takes a turn, that turn could be pushed to the other player. The other player can then make a move, that move would be pushed, and so on. Other examples are business apps that involve getting approvals from multiple people, especially when those approvals must be done in a certain sequence. Consider an expense report MIDlet. The app would push a request for approval to the first person. When the first person approves the report it is pushed to the second person, and so on. The report can be pushed back to the initiator if anyone declines to give their approval, or at the end of a successful approval process. Push functionality is useful to apps for which data updates are intermittently available, such as a commuter's helper that could receive weather and travel advisories. Screenshot shows another example, News Hound's news headline service. The service uses push functionality to provide interested users with a list of headlines of breaking news.

Screenshot News Hound Using Push Functionality

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Requests for help could also be written using push functionality. For example, consider a group of service technicians at customer sites. A technician having a problem could send a request for assistance to the group (in other words, it could be multicast). The technician could then accept the first offer of assistance. Finally, some MIDlet suites that are downloaded as demos could use push to register the suite and upgrade it to full functionality. The demo MIDlet would dynamically register the push connection. When the demo MIDlet received the receipt and key, it could make its full functionality available and unregister the connection.