Riding in Cars with UIs.

Exploring how drivers interact with digital car interfaces.

Rebecca Gordon
July 8, 2015

There's no shortage of discussion about car design and the future of car systems. But, for an environment in which so much time is spent multi-tasking each day, there is a lack of publicly available research into how drivers use the interfaces created for them.

As part of our ongoing research series into emerging and conventional usability standards, we wanted to explore how users are interacting with their in-car UIs. Sitting alongside and interviewing twelve drivers allowed us to identify features drivers care about, features they don't, and why certain features are consistently seen as more valuable.

This research is intended to initiate the further study needed to improve in-car experiences and establish best practices for designing car user interfaces.


How we tested.

As with all of our internal testing, we examined the behaviors of the general population. Over two days in a Rutherford, New Jersey parking lot, we spoke with twelve drivers, both male and female, whose ages spanned from 21 to 65. With a mix of different car makes and models, we were able to parse through the differences of the most popular digital interfaces no more than two years old. Through this, we began to understand user needs, expectations and frustrations with in-car interfaces.


Most features go unused.

Of the dozens offered, drivers tend to use only four of the UIs features: phone calls, music, navigation and rear-view camera, while the others go widely unutilized. The average vehicle has about thirty digital features, all communicating with the driver via the UI positioned in the center console. And far from a new development, the UI has gone from an audio-centric accompaniment to an all-encompassing travel partner.

Though features like voice command and Bluetooth are otherwise widely popular, drivers are often frustrated with their usability while in motion. Nearly each driver wanted the available features to work more seamlessly while driving but they don’t, and they each resorted to workarounds when finding the interface to be too difficult to operate.

Current interfaces have become an extension of the driver’s smartphone, rendering a mobile device–not the car UI–the epicenter of the in-car experience.

Current systems are way too complex.

Drivers find car user interfaces too complicated both to learn and use, and the experience left many drivers intimidated, and few explored beyond the few top tasks they wanted to learn. Users found multiple pathways confusing – buttons on the steering wheel, knobs on the center console and digital features – and admitted to using analog options instead of interacting with the digital system. The car’s buttons and knobs have been optimized over time for the in-car experience, and despite having digital options, drivers still fall back on analog because it offer a superior experience that has been designed and refined for in-car use over time. 

We found that current interfaces have become an extension of the driver’s smartphone, rendering a mobile device–not the car UI–the epicenter of the in-car experience. Likely a testament to the prevalence of poorly designed interfaces, all twelve drivers admitted to using their smartphones over their car UIs in order to complete even the most common task. Several drivers opting for phone-based GPS application because it easier to use and they trusted the mobile application more than their in-car interface.

Car UI 

Context is key.

Current in-car interfaces are not optimized for transient environments, and these systems are not suited for the attentional and physical constraints of driving. Safety can be compromised in a fraction of a second, and it is neither safe nor reasonably feasible for a driver to carry out the multitude of tasks that current in-car interfaces offer. In an environment where attention is dominated by the task of driving, interfaces need to be specifically designed with these limitations in mind.


Future research. 

More research needs to be done to explore how the tasks that are most important to users can be refined and improved, but based on our work thus far, we have a few recommendations. 

  • Account for the constraints of driving. In an environment where the ability to safely multitask is limited, it’s essential that manufacturers and designers have an empirically-grounded understanding of the risks of interacting with user interfaces while in motion. 
  • Understand the driver. By conducting user research, assess which tasks are most critical and valuable to drivers before designing user interfaces.   
  • Keep it simple. Before adding supplementary features to user interfaces, consider optimizing the few features drivers found most valuable, exploring low-cognitive load alternatives such as tactile or voice-controlled options.

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