If you haven't guessed from all the hoopla over the iPhone and the LG-Prada phone, graphics-rich touch-screen technology has evolved from kiosks, remote control user interfaces, tablet PCs and GPS devices to mobile phones. As you'd expect with any decent technology, it has an acronym - VDRM (visually rich, direct manipulation) - and it offers serious productivity gains, providing new capabilities and better visual engagement.
The trick, however, is in convincing the users of that. Creating the ideal touch-screen experience is challenging. Current VDRM apps aim to simplify hand-eye coordination, which would benefit multi-tasking users who need to devote their split attention between device operations and real-world navigating. That said, there can be serious drawbacks to mobile VDRM - finger stress, eye strain, lack of tactile feedback, and (as you'd expect) display smudges.
It's also important to keep in mind the problem VDRM is supposed to be solving. Take airline kiosks, where you can select your own seats by touching a color-coded seat map of the plane. No separate data entry is required and the seat is shown in context with the others.
For the airline agent, however, VRDM may become a burden. Agents already know the seating arrangement. Visuals can slow the interaction. It's actually easier for an agent to enter data with keystrokes.
That's why application designers need to be mindful of their users' familiarity, contextual knowledge and use frequency.
Think of fingers vs the styluses that Steve Jobs hates. If a touch-based application supports pushing finger-sized buttons, selecting icons or dragging objects, then a fingertip may be adequate for the task. But if input requires multi-stroke graphical characters, such as those in Asian languages, you'll likely need stylus support.
Proper touch screen design can certainly take the mobile experience to new levels. Creating a high-fidelity simulation of the familiar physical world can enable more intuitive experiences. Gesture-initiated scrolling, page-flipping and zooming are more satisfying when coupled with hand or finger movements that use gross motor skills. The experience can be further enhanced with perspective, reflections, lighting and shadowing to improve object identification, discrimination and understanding - provided product/app designers know when VDRM adds value to the user experience, and when it gets in the way of it.
Think of fingers vs styluses. If input requires multi-stroke graphical characters, such as those in Asian languages, you'll likely need stylus support