MEDL Mobile

JAWKU Speed & Your iOS Device

september 7, 2017

JAWKU App and JAWKU wristband next to running shoes

We recently worked with the team from JAWKU to release an app and wristband that allows high performance athletes to precisely measure and track their speed. This was a fun but challenging project, so we thought we’d share a little about what went into the development of JAWKU Speed.

The Challenge

Every great product starts with a well defined challenge. JAWKU’s target audience is athletes who are training for speed-based competitions, such as the NFL combine testing, where split-second accuracy is critical. These tests are often seen as the gold standard by recruiters and they measure the key physical achievements necessary for an athlete to compete at a professional level.

At the highest levels of competition, the difference between the top 1% of athletes and the rest is just fractions of a second. For this reason, the combine tests use high tech testing equipment to accurately measure athletes speed. 

The challenge for these athletes is simple: How can they prepare for the combines and measure their speed with near absolute accuracy using a stopwatch – which is only as accurate as the person holding it.

The challenge itself comes down to two key components:

  1. Accuracy – It’s difficult to understand your measurements if they’re unreliable. If you aren’t familiar with combine testing, a running back’s 40yd dash time can make or break their college career.

  2. Consistency – If you can’t depend on your results being consistent, it’s impossible to know if you’re improving. High performing athletes don’t train like the rest of us– it’s not about whether they did an extra lap today. They spend months trying to shave 1/10th of a second off their times. It’s critical that every measurement is consistent with the last so you know you’re progressing. A human with a stopwatch has too much variance, and it introduces an additional cognitive burden that distracts the athlete from putting 100% of their focus into their performance.


The Solution

To solve this, the JAWKU team came up with an idea to pair a motion sensitive wristband with an iPhone. The wristband records the exact starting time – and the iPhone creates a photo finish accurate to .01 seconds. 

When JAWKU came to MEDL, they had already built a proof-of-concept. But the interface was not yet designed for prime time, and the results were inconsistent. We worked with JAWKU to create a complete user experience that is not only seamless for the athlete – it actually creates a new visual language that quickly helps an athlete identify their speed and their progress. 

We also worked to fine tune the firmware solution to make sure the product was accurate enough for the serious athletes who would be putting it to the test.



Both MEDL and the JAWKU team are thrilled with the finished product. JAWKU Speed allows you to access professional training content, accurately measure your speed, and keep track of your running history to provide you with motivational results. Once the users wristband is paired with the app, an athlete can place their iPhone at the finish line, select their distance, and get moving. JAWKU will do the rest and provide you with your running time, reaction time, performance history, and notes. 

P.S. This was a very physical app to build. The whole MEDL team found it amusing to watch the QA team and the engineers run sprints in the parking lot in order to debug the software and put it through the paces. Although, our engineers weren’t fast enough to really push the device to the limit. Once we had things working properly it was time to take the testing to the next level. To ensure the accuracy we tested extensively against laser gate systems with JAWKU’s team of athletes.

JAWKU App and Wristband in action on the field

Get fast in 2 steps:

1. Buy the Wristband – 

2. Download the App –



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