As you develop your health app for the masses, one thing you probably have on your mind is to add HealthKit capabilities to your app. But, is it worth it?
Well it seems that many developers don’t think so. Consider the following…
I’ve got on my iPhone 24 apps that utilize HealthKit features.
20/24 of those apps allow for writing to HealthKit
14/24 of those apps allow for reading from HealthKit.
Apart from that, Fitbit, one of the biggest players in health tracking refuses to sync with HealthKit.


What’s the big deal?

This was perplexing and I didn’t understand it at first. Why would most of these apps allow people to write their data into HealthKit, but not read data into their app?


Writing Data To HealthKit


  1. Users can have all their health data in one place.
  2. Users can reuse their health data in other apps.
While those are great benefits for our users, some businesses see this as a disadvantage. Imagine you’ve been using your Fitbit for 1 year but a new device comes along with similar features to the Fitbit. Let’s call it Apple Watch. After buying the watch you learn that you can’t bring your Fitbit data into HealthKit or vice versa. What are you going to do?
Are you going to keep your Fitbit and ditch the watch or use the watch but lose a year worth of information. It’s an important dilemma. It’s so important that Fitbit has decidedly refused to sync with HealthKit. But is this the right move for your app?


Reading Data From HealthKit

Adversely, reading data seems to be a no brainer then right? If they have data that they are generating from another app and storing it in HealthKit, we want to bring that data into our app. This is extremely important and in some cases a deal breaker between someone using your app alongside another app or not using it at all. Because really, who wants to record the same data twice?

Not only that, but wouldn’t it be great to bring in all that data they’ve already generated and bring it into your app? Your user wouldn’t be starting from a blank slate, and instead would see all the benefits of your app instantaneously.
So how come most apps only allow for writing but not reading of data?
  1. Users who bring in HealthKit data to their app are restricted from storing that data in iCloud. If your app does this, Apple will reject your app. Apple does this because iCloud isn’t HIPAA regulated. It’s for that same reason that Apple doesn’t allow you to backup HealthKit data onto the iCloud and it is required that you turn on the encryption setting on iTunes when saving your backup onto your computer.
  2. Reading data from HealthKit can put your app at risk if the data that is being read isn’t consistent with the context of your app. Imagine if your app only stored your heart rate at rest, but HealthKit only contains your heart rate during a strenuous exercise. They are not comparable and now you have data that could ruin your user’s experience.


Don’t Forget About Marketing

Now that we have an idea between the pros and cons of reading and writing to HealthKit, there’s one more thing to consider. By integrating HealthKit in your app, this can open up a dialogue between you and Apple to be featured in the HealthKit category. It’s not a given, but obviously a prerequisite, and if you’ve got a good app, you may have just found another way to get more eyeballs on your app. 


Wrapping it up

In the end the decision is up to you. Consider your short and long term goals. Determine whether it is important to integrate HealthKit now or a few months from now. Determine if HealthKit is a critical bottleneck between users using your app or if it’s as risky as Fitbit sees it.