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(Taken from TI education site)
Introduction of Flash Technology
As TI continued to work with educators, they indicated the desire for a way to add more capabilities to the handheld units they've already invested in. At the same time, Flash memory technology, which allows the calculator's software to be upgraded electronically, became affordable. As a result, TI pioneered the use of Flash technology in the educational arena by incorporating it in the graphing units.
In just 13 months, TI developed a line of Flash-based handheld tools and add-on calculator software applications (Apps). In 1998, TI introduced the TI-73 with Flash technology for middle grades, then quickly incorporated the technology into the TI-83 TI-83 Plus and the TI-89 and TI-92 (TI-92 Plus).
Benefits of Flash Technology
Educators stressed that flexibility was key in any product TI developed. With the addition of Flash technology, users have the ability to upgrade the functionality of their units by installing current and future calculator software Apps. Using a cable attached to a computer, application software can be updated with the latest operating systems or new software Apps. This enables users to customize their graphing units to support their curriculum.
From "Topics in Algebra I," which provides specific curriculum topics, overviews, and supporting activities to "Inequality Graphing," which provides additional capabilities to support important concepts, the variety illustrates the depth and breadth of software Apps that are available to TI users.
The popularity of TI graphing products has attracted the interest of third-party developers, a number of whom have created Apps for the TI Flash-based products.
As TI continues to listen to educators and work with them on their needs, the company will continue to develop practical educational technology solutions that help increase teacher and student success.
Flash Apps
Introduced with the 83+ and 73 is the capability to use assembly-based application programs stored in pages of its flash memory, or flash apps. These allow a whole new dimension to TI calcs. Third parties can program programs that you can (ideally) purchase and load onto your calculator, extending its function in some way. This is similiar to buying programs for your computer and loading them on. Flash app capability is currently limited to the 83+ and the 73; updated versions of the 89 and 92+ will soon support them.
Flash apps have he potential to bring significantly new capabilities to TI calculators and therefore increase the number of people who could find them useful. Examples include sheduling capabilities, a word processor, games, or whatever else the imagination allows. A few are available now, but development is in its early stages. All flash apps can be purchased and downloaded at TI's web site.
What prevents purchasing one copy and putting it on your friends' calculators as well? The apps won't run on them. Each flash app-capable calculator has a built-in ID, which you must provide when buying an app. The app is "signed" and encrypted to only allow it to run on the IDs it was purchased for. It needs a matching ID in order to run. A similiar scheme is used on SGI workstations. Shareware and freeware apps can be signed to run on all calculators. Keep an eye on the available apps, I think you will find many of them worth the price.