For certain applications a touch screen is the unparalleled best interface available1, however, it is worth being aware of the alternatives that may be suitable for other applications. I group the alternatives into three categories:
- Other devices, eg mouse, trackpad, smartphone.
The obvious benefit of being able to use gestures is that the user doesn’t need to touch the display, great for germaphobes, useful for situations where reaching a screen isn’t convenient (from a car window, from a sofa, from behind a barrier), and also possibly suitable for video walls where the display surface is very large. Of course, they can also be very appropriate for games.
On the downside is accuracy, erroneous interpretation of gestures, and the lack of an intuitive gesture language.
Voice interactivity is definitely a viable option for certain applications as consumer voice interfaces like Siri and Alexa ably demonstrate. There are many choices for adding voice and these can be tailored to the specific application which can improve accuracy of comprehension.
However voice is not suitable for many of the functions that make a touch screen so useful. For example selecting a point on a display, no one wants to have to go through a “up a bit, left, up a bit more” and so on kind of exercise every time they want to select and area, or zoom in on an area.
Clearly the keyboard and mouse or trackpad (or joystick type devices) are the ubiquitous user interface for working with a computer and display though as smartphones have shown, touch screens can readily enable them to be replaced.
Smartphones are probably the most obvious other devices. Most people have them, they have touch screens and they are personal. The main downside is that they are small, so the benefit of a touch-screen on a 55″ display is lost if you are using a 5″ display as the touch interface. Having said that there are definitely applications where it can be suitable, for example, I have used the smartphone touch screen as my interface for a presentation on a large display at the front of a meeting room. Also, many people would rather use their phone than touch the screen of a terminal in a retail setting.
As smartphones have very clearly shown, with the right software a touch screen is an incredibly powerful and versatile user interface. However other user interfaces are definitely suitable depending on the application and the environment.
Note 1: For reviewing plans, maps and similar visuals the ability to pan and zoom an image is essential and a touch screen wins hands down as the ideal user interface. Combined with a larger display the user not only gets to see more but also has unparalleled ability to navigate an image.