More than Touch

More than Touch proposes guidance for future researchers and developers in designing on-skin interaction techniques, as little previous work has empirically investigated input on skin. Miniaturization in electronics have enabled the expansion of smart watches and other wearables, The researchers of More than Touch suggest these devices offer too little surface area for effective touch input; expanding interaction to utilize the surface of skin, however, would provide a large touch surface. Skin has great potential to act as an accompanying surface for wearables.

The researchers worked with 22 voluntary participants, 11 males and 11 females, and asked each participant to define a set of skin-specific touch gestures. These user-defined gestures were categorized based on input modalities, location on the body, and properties of the gesture, such as pressure, speed, contact area, etc. The gestures were then separately classified as skin-specific if the gesture incorporated a modality that could not be replicated using simple multi-touch input. This would include inputs involving pinching, twisting, or scratching.

Pinching, scratching, and twisting gestures

The list of gestures collected is quite impressive with on-skin gestures ranging from common command like force close, select, and help, to complex emotions like sympathy, boredom, and anger.
List of gestures as defined by More than Touch
Using the Technology Acceptance Model, or TAM, we can predict how likely people are to use an innovation through the analysis of perceived usefulness and perceived ease of use.

Perceived Use/Comfort of Touch

The researchers in More than Touch examined participants perceived ease of use and the perceived comfort of the gestures. Each participant rated the comfort and ease of use on a separate Likert scale. All input gestures performed on skin were perceived as being rather easy to perform. The means for perceived comfort of use followed the same order, with somewhat lower means.

Bar chart from More than Touch illustrating perceived ease and comfort are closely correlated for each gesture.

The only outlier was scratching. This is explained by qualitative feedback: although participants did not perceive scratching as physically uncomfortable, it was perceived as a socially unaccepted and awkward input modality: “I feel like a monkey.” Uncomfortable interactions were chosen for actions that are very important and not reversible. For example, participants defined an uncomfortable gesture for permanent deletion and force close, some even going as far as noting “it should be painful to do this.”

Painful gestures as defined by More than Touch

The Six Regions for Touch

The researchers were able to identify six areas on arm where users defined gestures: the forearm, back of the hand, palm, fingers, the upper arm, and the elbow. The forearm was the most used area accounting for 50% of gestures defined.

Arm regions as defined by More than Touch

Pie chart illustrating the breakdown of gestures by region.

Emotional Gestures

Emotion played a large role when participants defined the location for skin-specific gestures. For instance, the palm was explicitly preferred by 41% of participants for private interactions because the hand can be concealed; “We used to write on the palm for cheating in an exam. It’s possible to hide things there”

<img alt="Cheat-your-Way-Through-Life" src="//" style="max-width:100%;"//>

The palm also tended to be associated with positive actions, while the back of the hand was associated with negative action. The gesture for accept a call was performed more than twice as often on the palm (36% of participants) than on the back of the hand (14% of participants). Users defined intense emotions, such as anger, with uncomfortable gestures even through participants were interacting with their own skin, the user-defined gestures tended to involved a bit of pain.

<img alt="Variations of the anger gesture." src="//" style="max-width:100%;"//>

Intuitive Input

Results of the study show participants intuitively made use of the added possibilities provided by on-skin input. Think about that. It is possible for users to perform more expressive gestures to better convey the command simply by leveraging physical affordances specific to skin and by taking inspiration from the way we interact with other people using touch!

On-skin Affordance for Wearables

The findings of More than Touch conclude that on-skin input is most compatible with wearables like smart watches because the forearm and the hand are most preferred locations for on-skin input; both areas are in direct vicinity of a smart watch like device. We can look at the trend of wearables to expand upon the adoption of skin as a companion interface for these devices.

The Perception of Wearables

The 2014 white paper, The Internet of Things: The Future of Consumer Adoption, outlines the current perceptions and future adoption of wearable technology. It turns out that wearable fitness devices are slated to see the most growth: 33% in next 5 years, as compared to smart watches 5% next year, 23% in next 5 years. The biggest challenge for wearables is overcoming a lack of perceived usefulness. This report shows 30% of people polled didn’t see the value of using a wearable device.

According to another Business Insider report on the smart watch market, 51% of individuals polled simply didn’t see the point of a smart watch. Furthermore, 26% polled were concerned with privacy and the implications of sharing personal information without their control. It appears our culture is still skeptical adopting technology that collects and shares information. However, these concerns are short term, as 65% of consumers plan to adopt the tech as some point once the issues of privacy and lack of functionality are solved.

Utility over Novelty

Additionally, consumers stated they would be more likely to pay a premium for a smart devices offering safety (utility) over novelty, as 83% were willing to pay more for a smart alarm, than 59% that would purchase a smart refrigerator.

In order to permeate the market, wearables need to be perceived as a utility and persuade users on its functionality. That is, without crossing the line into “creepy.”

Google Glass as a study

For an example of a wearable technology that both failed to prove its usefulness and became social unacceptable, let’s look to the infamous Google Glass.

google-glass ad

Google Glass is an exquisite case study on how a wearable, even with an innovative interface, can fail. With the use of hindsight and TAM as a basis of analysis, we can identify its faults. A Statista report on US Consumer’s views on the use and adoption of Google Glass shows that 45% thought it would be too socially awkward and 44% didn’t fund any of the features appealing.


Even though skin appears to be a viable surface for interface, it is far too early to predict the adoption of this technology. Smart watch technology is also early in its adoption, and the general population has not been convinced of its usefulness outside of passive monitoring for medical means. While the usefulness of smart watch features is not currently visible enough for strong adoption, it appears people are slowly warming up to the technology as it become more mature.

Once wearable devices becomes more widely adopted and integrated into our culture, on-skin interfaces will be a natural evolution of the technology. I believe More than Touch is an essential contribution to the emerging field of on-skin interface and provides ample guidance for future research. It’s a fantastic paradigm-shifting read that will change the way you perceive tactile feedback for wearables.


If you are looking for insight into the future of touch interfaces, look no farther than your own arm.