Privacy Policy

1. Who we are

Split Index ("we", "us", or "our") operates the Split Index fitness analytics platform at splitindex.co.uk. We are the data controller for personal data processed through the service.

For privacy-related enquiries, contact us at privacy@splitindex.co.uk.

2. What data we collect

We collect and process the following categories of data:

• Account information: email address, authentication identifiers, and profile details such as username, display name, avatar, and country.
• Health and fitness data: workout and activity logs (including sport type, duration, distance, pace, heart rate, and gym exercise data), body metrics (such as weight and body fat percentage), recovery metrics (such as sleep, HRV, and resting heart rate), training goals, and performance scores including your Split Index.
• Onboarding and preferences: age, height, weight, gender, experience level, training history, and preferred sports.
• Precise location and route data: when you start a GPS session in the mobile app, we record your precise location repeatedly for the duration of that session and store the resulting route. With your permission this continues in the background, while your phone is locked and the app is not on screen, because that is what recording a run requires. We collect location only during a session you have started, never passively, and you can stop it at any time. You can also set a privacy zone so the start and end of routes near a chosen address are trimmed before storage.
• Apple Health and connected sensors (mobile app): with your permission we read heart rate from Apple Health during a session — including from AirPods Pro — and start a HealthKit workout session so that sensor turns on. We also connect over Bluetooth to heart-rate straps and compatible equipment such as the Concept2 PM5, and read motion and step data to calculate your cadence. Each of these is optional, is asked for separately by iOS or Android, and can be revoked in your device settings without losing your account.
• Payment information:subscription status, billing history, and payment-processor identifiers. On the web, payment card details are collected and processed directly by Stripe. In the iOS and Android apps, purchases are made through Apple's In-App Purchase or Google Play Billing and are recorded for us by RevenueCat; we never see or store your card details in either case.
• OAuth data:when you sign in with Google or with Apple, we receive the account identifiers you authorise through that provider. Sign in with Apple lets you hide your real email address; if you do, we only ever hold Apple's relay address.
• Social features: friend connections, leaderboard participation, and public profile information you choose to share.
• Technical and usage data: IP address, browser type, device information, cookies, and logs related to how you use the service.
• AI-generated content: workout analysis and coaching feedback generated from your activity data.

3. How we use your data

We use your data to:

• Provide, maintain, and improve the Split Index service;
• Calculate performance scores, analytics, and personalised insights;
• Process subscriptions and manage billing;
• Authenticate your account and secure the platform;
• Import and sync activities from connected fitness integrations;
• Enable social features such as leaderboards and shared profiles;
• Generate AI-powered coaching feedback based on your workout data;
• Communicate with you about your account, updates, and support requests;
• Comply with legal obligations and enforce our terms.

If you sign in with Google, we use the Google account information you authorise (such as your name and email address) solely to create and authenticate your Split Index account. We do not use Google user data for advertising, and we do not sell your personal data.

4. Legal bases for processing (UK GDPR)

Under UK data protection law, we rely on the following legal bases:

• Contract: processing necessary to provide the service you sign up for, including account management, scoring, and subscriptions.
• Consent: where you connect third-party integrations, enable optional features, or agree to marketing communications.
• Legitimate interests: to improve the service, prevent fraud, and maintain security, balanced against your rights.
• Legal obligation: where we must retain or disclose data to comply with applicable law.

Health and fitness data may constitute special category data. Where applicable, we process this data based on your explicit consent and/or because it is necessary for the provision of our fitness analytics service at your request.

5. Third-party service providers

We use trusted processors to operate Split Index. They may process your data only on our instructions and subject to appropriate safeguards:

• Supabase — authentication, database hosting, and file storage;
• Vercel — application hosting and content delivery;
• Stripe — payment processing and subscription management;
• Google — OAuth sign-in (when you choose to use it);
• Apple — Sign in with Apple (when you choose it) and In-App Purchase for subscriptions bought in the iOS app;
• Google Play — billing for subscriptions bought in the Android app;
• RevenueCat — recording and validating mobile subscription receipts from Apple and Google;
• OpenAI — AI-generated coaching feedback based on your workout data.

Your location and route data is not shared with any of these providers beyond the hosting and database services that store it, and is never sold, shared for advertising, or used to build a profile of your movements outside the sessions you record.

Each third party operates under its own privacy policy, and each is bound by a written agreement requiring them to protect your data to a standard at least equivalent to the one described in this policy, to process it only on our instructions, and to apply appropriate technical and organisational security measures. We encourage you to review their policies when connecting external accounts.

6. Cookies and similar technologies

We use cookies and similar technologies to keep you signed in, remember preferences, and understand how the service is used. Essential cookies are required for authentication and core functionality. Where non-essential cookies are used, we will request your consent in line with UK requirements.

You can control cookies through your browser settings. Disabling essential cookies may prevent you from using certain features, including sign-in.

7. Data sharing

We do not sell your personal data. We may share data:

• With service providers listed above, to operate the platform;
• With other users, when you use social features or set your profile to be publicly visible;
• When required by law, regulation, court order, or to protect the rights and safety of Split Index, our users, or others;
• In connection with a merger, acquisition, or sale of assets, subject to appropriate confidentiality protections.

8. International transfers

Some of our service providers may process data outside the United Kingdom. Where this occurs, we ensure appropriate safeguards are in place, such as UK adequacy regulations, Standard Contractual Clauses, or equivalent mechanisms recognised under UK GDPR.

9. Data retention, deletion, and withdrawing consent

We retain your data for as long as your account is active and as needed to provide the service.

You can delete your account and all of its data from inside the app, under Settings → Delete account. Deletion removes your profile, every logged activity and route, your scores and index history, your social connections, and your training plans. It takes effect immediately and cannot be undone. We retain only what we are legally required to keep for accounting and fraud-prevention purposes, which does not include your training or location data. You can also request deletion by emailing privacy@splitindex.co.uk.

Withdrawing consent does not require deleting your account. Location, Apple Health, Bluetooth and motion access are each granted separately, and each can be revoked at any time in your device's settings — on iOS under Settings → Split Index, on Android under App info → Permissions. Revoking one stops that collection from then on and disables only the features that depend on it; everything you have already logged stays yours and remains available. Disconnecting a third-party integration in Settings stops any further import from that provider.

Deleting the app from your device does not delete your account, because your data is held on our servers rather than on the phone. Use the in-app deletion above, or email us.

10. Your rights

Under UK GDPR, you have the right to:

• Access the personal data we hold about you;
• Request correction of inaccurate data;
• Request deletion of your data in certain circumstances;
• Restrict or object to certain processing;
• Request portability of data you provided to us;
• Withdraw consent where processing is based on consent;
• Lodge a complaint with the Information Commissioner's Office (ICO) at ico.org.uk.

To exercise your rights, email privacy@splitindex.co.uk. We may need to verify your identity before responding.

11. Security

We implement appropriate technical and organisational measures to protect your data, including encryption in transit, access controls, and row-level security on user data. No method of transmission or storage is completely secure; please use a strong, unique password and keep your credentials confidential.

12. Children

Split Index is not intended for users under 13 years of age. We do not knowingly collect personal data from children under 13. If you believe a child has provided us with personal data, please contact us and we will take steps to delete it.

13. Changes to this policy

We may update this Privacy Policy from time to time. We will post the revised version on this page and update the effective date. Where changes are material, we will provide additional notice where appropriate.

14. Contact

Questions about this Privacy Policy or our data practices? Contact us at privacy@splitindex.co.uk or support@splitindex.co.uk.