Top 10 Fitness APIs: Apple Health, Fitbit and Nike

We saw 2014 bring in an extraordinary rise in interest and popularity in fitness-related apps, with the market set to continue the mammoth growth into 2015 and beyond. According to Flurry, health and fitness apps grew by 62% in the first two quarters of 2014, compared to the 33% general average.

Flurry stats

We will be seeing the big players, from Apple, Google and Samsung, to Fitbit, JawBone and Nike+. The market is certainly primed for vendors for intense competition to gain the choice among users whom are really keen to track their fitness and health more proactively and tangibly. The APIs in our list scored well against the following criteria:

  • Popularity
  • Potential
  • Documentation
  • Ease-of-use
  • Functionality

We also provide you with insight through Google Trends on the search-engine popularity of each API.

Apple Health

Link: /api/apple-healthkit
Provider: Apple
API Documentation URL:

Apple announced they are taking on the health industry with one of their iOS 8 SDKs, Apple Health, announced mid–2014, is Apple’s effort to centralize and aggregate all user health information from various health apps and health accessories, such as Fitbit. While still in it’s infancy, Apple Health has shown an incredible amount of interest according to our analytics, as well as continuing and constant chatter on Google Trends.

This trend will certainly continue to gain more of a foothold, thanks to the growing interest in health, as well as the launch of Apple Watch. By all indications, the wearable fitness market still has a while to grow. 

The API is in its first iteration and while we will likely see some fixes here and there (for instance the glucose tracking had been temporarily disabled after some bugs were found) we saw Apple’s potential to garner wide community support as unparalleled despite being the newest entrant to the health market. The SDK is relatively easy for existing iOS developers to implement, based on existing patterns, but we were disappointed to see that the SDK is not cross- Platform, nor is a RESTful API offered.

Apple Health exposes more than merely fitness or activity-tracking, but a means to track nutritional information, as well as medical measurements such as glucose, blood pressure and cholesterol and thus we have decided to also include it as part of a few of our other Top 10 list categories.

Link: Google Trends


Provider: Fitbit
Documentation URL:

Fitbit had a public spat with Apple after publicly stating they would not support HealthKit. Fitbit provides an SDK for tracking personal health information such as total sleep and activities, and while Fitbit has been around for some time, their SDK is also relatively new.

Fitbit has the advantage of having released numerous wearables to track activities and sleep and has thus has built a bit of a community. Documentation on Fitbit is quite substantial, with examples in .NET, PHP, and various client libraries. Being cross-platform and an API rather than an SDK, it does win some points over Apple, but it will be very tough for any vendor to overtake Apple in a maturing market.

Link: Google Trends

RunKeeper Graph

Provider: RunKeeper
Documentation URL:

RunKeeper offers a more mature API than both Withings and Fitbit, as a software-only health product. RunKeeper exposes API methods to track everything from blood pressure to glucose, and virtually all forms of health measurements.

With Apple Health entering iOS, it will certainly take away a lot of the API uniqueness offered by RunKeeper, although their app remains quite popular. Google Fit may eventually erode its API popularity on Android, which may be a cause for concern as far as attracting third party developers to use RunKeeper as their health information conduit.

We certainly love how extensive their API is, and along with the Sample Code they provide, is of distinguishable high quality.

Link: Google Trends


Provider: Nike
API Documentation URL:

Nike+ is a software solution from fitness-giant Nike that has widespread popularity among users, and has had a close association with Apple since the first iPod, providing tracking pedometers for shoes, as well as fitness watches. Their iOS app has also been quite popular for tracking running and walking activities. They have recently made a huge push towards developer-involvement with a new API and Developer Portal, so they have really gone gung-ho in terms of community-engagement.

They currently provide a RESTful API, iOS and Android SDKs, as well as a JavaScript SDK, all capable of accessing raw data, including GPS data. Their level of documentation, as well as ease-of-use is commendable. They also feature a test console in their developer's toolkit, something that is overlooked by too many vendors.


Link: Google Trends


Link: /api/withings
Provider: Withings
API Documentation URL:

Much like Fitbit, French-based Withings provides a wide array of hardware accessories, although with a more extensive range. From Wifi-powered body weight-scales to activity trackers and home cameras, Withings is renowned for being more hardware-based.

Utilizing their widely popular accessories, their development focus is on being able to expose web services that in turn expose hooks to their products, from being able to directly acess information from scales, blood pressure information and various other user data.

The API is more limited in terms of functionality than Fitbit’s, and does not provide as user-friendly documentation, nor readily-available sample code.

Link: Google Trends

Google Fit

Provider: Google
API Documentation URL:

Google had discontinued a similar venture, Google Health, back in 2011. Late last year it went ahead and launched Google Fit, in direct response to Apple’s Health initiative. With Android watches already on the market, they do have a head-start as far as hardware goes, but the key will be in how quickly developers use Google’s APIs. Large Android manufacturers like Samsung already have their own health apps and SDKs, with S-Health, and may be too reluctant to embrace Google’s SDK in lieu of theirs.

In terms of functionality, Google Fit provides similar features to Apple’s HealthKit, we are still on the fence as to whether the giant’s foray into fitness will gain traction, because of said reasons.

We can also forgive Google for not having the most complete documentation, having only recently been released, and we'll have to wait until Google I\O to see the project move forward at a faster-pace. Having said that, they have provided a great Getting started on Android section along with some helpful videos to get people started.


Link: Google Trends

JawBone Up

Provider: Jawbone
API Documentation URL:

Jawbone, much like Fitbit, develops accessories such as the Jawbone UP wristband and app that aid in tracking sleep, movement and eating patterns. Jawbone expose the UP platform through their development API, as well as an SDK for native app developers.

Similar to other vendors on this list, Jawbone allows for aggregation of data, with two-way API communication, and OAuth Authentication protocol mechanism.

While UP is not rated as highly as some of the other APIs on the list, it does have potential to rise in the near-future. It possesses decent documentation, albeit arranged in a slightly less-convenient manner compared to others. It also provides good sample code, as well as a client-side SDK for both iOS and android.

Link: Google Trends


Link: /api/mapmyfitness
Provider: MapMyFitness
API Documentation URL:

MapMyFitness has one core-competency and that’s to create the world’s largest API conduit of health and fitness-tracking information. The vendor runs a network of sites, such as MapMyWalk, MapMyRun, MapMyRide, MapMyTrip, MapMyHike and MapMyMountain, separating activities into individual specialized sites. MapMyFitness was acquired by UnderArmour about a year ago.

MapMyFitness provides a rich set of API hooks, including social Integration. API integration is through XML, JSON, PHP and text, with OAuth authentication, as per industry standards. The documentation available is quite extensive and clear, along with an online Sandbox to test out the various API methods. The API is quite social-driven, allowing for tracking of events that friends of users take part in.

MapMyFitness had traditionally been one of the largest API communities with over 20 million registered users (9 million active users) according to TechCrunch, prior to it’s acquisition, and has since been collaborating with large companies such as Samsung and their wearable gears. In 2012 it’s MapMyRun app for iPhone was regarded as one of the top running apps, however pushes by Nike+, Fitbit and RunKeeper have dimished some of the the app’s popularity.

Link: Google Trends


Link: /api/moves
Provider: Moves
API Documentation URL:

Moves is a software-only company and not as strong an offering as some of the other vendors and solutions. The Moves API is similar to the other vendors in providing automatic recording of multiple activities. 

Their API is quite bare-bones in terms of documentation, although they provide access to some third-party client libraries that work with the API. It's not clear what the future holds, due to the fact they don’t seem to have a large community of developers that they can piggy-back off to grow, nor the leverage of Nike or Apple to be able to generate instant-interest.

Link: Google Trends

Wahoo Fitness

Link: /api/wahoo-fitness
Provider: Wahoo Fitness
API Documentation URL:

Wahoo Fitness offers the same sort of functionality as the rest of the list along with an array of hardware sensors such as weight scales and running/cycling sensors. Whilst the actual functionality of Wahoo Fitness is comparable with others, it's extensibility on par with the best, the developer documentation pages aren't as impressive by any means.

That is, they offer a basic retro JavaDoc style portal to all the classes available, as well as those that are deprecated, and it doesnt do much to inspire developers. They would do well to provide more of a community, sample projects, in-page API testing, and forums, along with a UX-revamp if they are looking to build a better rapport with developers. 

Link: Google Trends



Be sure to read the next Fitness article: How Garmin Offers Developers Nearly Limitless Possibilities for Lifestyle Quantification