I really want an interface designed with usability in mind. Things like:
* No common task should require more than 3-4 keypresses you can easily remember. Arrow keys count. Corollary: navigate the menus with the number keys; shortcuts, ...
* Incremental search to look up contacts with (like emacs C-s)
* Operate without looking. In particular, there should be a way to get to "home" from an arbitrary state, options have a "return to default" key, all important menus stay the same, anything common/important can also be done by keyboard.
* Typing speed. With slow input, calendar functions etc are nearly useless. Unfortunately, the fastest solution, qwertz keyboards, still sell at a premium. Perhaps there is a way to optionally emulate a chorded keyboard on standard 12-key hardware? It should have some form of visual feedback enabled by default, like Apple's keyboard overview.
* Reliable Sync. Even with 348 contacts, 1000s of appointments, international characters. The point is reliably correct - everything I have had so far has messed up eventually.
* Todo list and calendar 2 taps/clicks away, such as for a shopping list
Besides, I'd like some gimmicks:
* Adjust lighting / color hue / contrast on images, cut them down to an image section. Cut videos to save space and improve art.
* Easy file sync, regardless of file format
* Track location over time and tag photos. Even if there is no GPS hardware, cell towers broadcast their ID (or location), and modern phones have an acceleration sensor.
* A 3-touch way to keep track of my money / time.
* Office to go
* Flashlight mode. Display lighting is usually bright enough to find the key hole, stuff I have dropped,...
I admit you asked about computationally intense applications, but this is what bothers me most about my gadgets.
