What Twikka does with your health data

What does Twikka read from Apple Health or Health Connect?

If you allow it, Twikka reads your steps and workouts from Apple Health (iPhone) or Health Connect (Android), and you can turn this off at any time in your phone's settings. What holds for any app is that it asks your permission first, and you decide what to allow.

On an iPhone, Apple Health can show steps taken today, how often you move and how often you stand up⁴. With a smartwatch it can also track heart rate and sleep quality, and track activity all day rather than only when you carry the phone⁴. Apple gives separate permissions to separate sensors, so you can allow one kind of data and refuse another¹.

Some apps ask for very little. One walking app from a national health service makes syncing with Health Connect optional, reads only your step count and says it accesses no other health information².

Once you have given permission, an app can download and upload data without asking you again⁵. That is why it is worth reading which data types an app wants before you agree.

Step count shows how much you move in a day, not how well you walk. It is also shaped by things like weather, appointments and opportunity to walk⁶.

Who can see your health data?

It depends on the app, and health and fitness apps can pass data to other companies. Some companies share the data they collect with advertisers, insurance companies, employers and data brokers, and not all make this clear¹. Some apps pass data to third parties that have their own policies, and leave you to decide about sharing yourself³.

Apps also collect more than health numbers. Privacy policies can cover device identifiers, IP addresses, location and how you use the app, which can reveal things unrelated to health¹. Many health apps need personal data before you can use them, and it may be used to personalise advertising. Most people are unlikely to know the full extent of what is collected⁷.

You have some protection. Good practice for health apps includes encryption, secure sign-in and regular risk assessments. Under the EU's GDPR you have the right to access, amend, delete or restrict processing of your data⁸. People also say they want a clearer understanding of who else can access their health information and how to control that access⁸.

What to do:

• Look for a plain explanation of who your data is shared with, and whether you can choose what is shared.
• Check other companies' policies if an app says it passes data on.
• Leave out health conditions if an app doesn't need them.

Can you disconnect your health data?

Yes. You can take back an app's permission through the health permissions on your phone. In Health Connect on Android you can revoke access at any time in its settings². Some apps can also be used without an account, in which case activity data stays on your device².

Disconnecting may stop only new data being collected. Data already shared can stay with the app or its affiliates, and some may still be used in anonymous form for research³. Deleting what has been collected can be slower: requests to delete personal information or close an account can be lengthy (an average of 30 days in some apps) and conditional, with no guidance on when data collection stops³.

How easy it is varies from app to app. One app explained its deletion process clearly and aimed to remove all of a user's data within 30 days. Others gave no easy way to opt out of sharing or to delete an account from within the app³. In some apps the rights to ask for deletion or to object to the use of your data are not absolute, because continued use is sometimes necessary².

Before you rely on an app, check whether it explains how to delete your data and how long that takes.

When to check with a health professional

Follow your doctor's advice over anything an app suggests. Data from fitness devices and apps can be less reliable than data from approved medical devices, so treat it as a rough guide to your activity, not a medical measure⁵.

If you're starting exercise after a long break, it's always a good idea to see your doctor first. For an injury or a health condition, see a health professional, such as your doctor or a physio.

Call your local emergency number for chest pain or pressure (or pain spreading to the arm, neck, jaw or back, especially with sweating or feeling sick), severe breathlessness, fainting or collapse, signs of a stroke, a serious injury, or someone who isn't safe.