Unless a dramatically better way is found, mobile software will never be really usable: compared to a PC, data entry is several to many times slower (depending on whether there's a full keyboard on the mobile device or not etc.), and the equivalent of the highly effective mouse pointer is simply not there.

But Situational Software could be that dramatically better way, because it enables the device to know so much already about both the user and their situation, and that can be used to dramatically reduce the amount of data entry required. Here are some examples:

• Instead of finding the "start" menu, selecting an application and running it, logging in, and clicking through the application (as in case of traditional, application-centric software), situational software can simply show the right screen already! No typing required.
• Instead of moving back and forth between applications, or even between different screens in the same application, situational software can automatically do that in many circumstances.
• Instead of having monstrous menu bars with endless pulldown menus, tool bars, etc. — they are needed because traditional application software does not know what situation the user is in and what they want to accomplish — Situational Software can dramatically reduce this amount to the only operations that actually make sense in a given situation. I just counted: my version of Microsoft Word has several hundred menu items — what about getting rid of all of them except for the ones that make sense for my current situation?

Of course, none of this means that situational software cannot have hundreds of menu items. The point is that it does not need them, in most of the cases, and that's quite exciting, particularly for mobile users with small displays and less capabilities for high-speed data entry.

Here is the real-world analogy: if you have a secretary or assistant who really knows (and cares) what situation you are currently in, there is never a need for them to offer to you at any point in time more than a few of the hundreds of different activities that they are capable of performing. Instead, they know what your current situation is, try to anticipate what you are trying to accomplish, and offer you assistance for your particular situation. And thus are orders of magnitude more useful than an assistant who does not know or does not care what situation you are currently in. It's just the same with situational software compared to traditional application software.