The wearable tech industry is maturing at a rapid rate, with more brands entering the fray and demands for functional design - that also looks good - raising the stakes.
During Baselworld 2016 smartwatches were the big story as Tag Heuer's Android Wear collaboration, Michael Kors' Access smartwatch and Fossil's new smart analogue devices with activity tracking and smart notifications stole the show.
Of course watches aren't the only wearables - smart glasses, smart rings or other jewellery, devices that can be attached to your clothing, augmented reality helmets and health, diet and fitness monitoring trackers and wristbands that (sometimes) interact with other devices on our bodies while we interact with them, are all readily available.
All wearables need a consumer-friendly UI with functionality, usability and style appeal being the three most important design demands.
Swiping, pinch-and-zoom, tapping, and haptic technology (the science of applying touch (tactile) sensation and control to interaction with computer applications) describe the ways users will interact with the wearable tech and additionally influence design decisions.
The Sony Smartwatch 3 displays one 'idea' at a time
If designing for mobile was challenging, wearables are even more so. Phone-based watches such as Samsung Gear S2 and Apple Watch, or activity trackers such as Fitbit Surge all come with screens that are only a few millimeters in size.
Making good use of the available space is imperative, and ways to do this is to keep things uncomplicated. For instance, display only one message per screen, keep to a low character count, omit unnecessary words and balance content with micro-interactions.
The Samsung Gear S2 uses colour to differentiate between functions
Most wearables use simple fonts such as sans serif that are easy to read. A simple font and only displaying between 15 and 20 characters per line and up to a maximum of 7 lines per screen makes the information easy to read and act on.
By using different font sizes, designers can draw the user's attention to less or more important content.
High contrasting colours
Black or dark brown are often used as background colours as they make bright hues really pop. Strongly contrasting colours also enable the user to easily see and interact with different icons on the screen.
Different colours are used to resemble different functions on the app, for instance orange could be for user actions and blue for branding. Don't use more than three colours and avoid colour gradients.
The Fitbit Blaze uses a dark background and varying font sizes.
Engage senses other than visual
Non-visual communication tools are the way of the future and means you have to increasingly consider feeling and hearing along with looking.
For instance, vibrations can tell you which way to turn while voice dictation can be activated to compose messages and text.
Gestures are also an important element of activating applications.
Multifunction features are also important. Apple Watch's Force Touch, for instance, can sense the difference between a long-press and a simple tap.
Mirror that brand's design on other devices
It goes without saying that the brand's corporate identity (CI) needs to be carried over to the confines of the wearable's design.
This means colours, fonts and icons need to be instantly identifiable with the brand and in some cases this makes designing the UI really easy; in others presents restrictions that need a lot of thinking to overcome.
The Microsoft Band 2 has taken simplicity to a whole new level
Finally, always keep the user in mind. Users expect the device to perform according to their demands and don't want to struggle with a fiddly interface that requires multiple actions to get to what they want to do.
To this end, consider allowing the user to customise the watch interface to suit their needs so that the device becomes more useful to them.
And don't forget the power or voice commands and vibrations - two tech functions that leave you with more space for the applications and functions that are dependent on display.