Legal
Privacy Policy
1. Who we are and what this covers
GrindSplit LLC ("GrindSplit," "we," "us") makes the GrindSplit athlete training app. This policy explains what we collect, why we collect it, who receives it, and the choices you have.
- Legal name: GrindSplit LLC
- Mailing address: 14 Industrial Ave, Mahwah, NJ 07430
- Privacy questions and requests: privacy@grindsplit.ai
- Support: support@grindsplit.ai
This policy covers the GrindSplit iOS app, the Apple Watch app, our widgets, and the website grindsplit.ai.
GrindSplit is offered only in the United States. You must be at least 13 years old to use it. If you are 13 to 17, you should have a parent's or guardian's permission (see section 9).
GrindSplit handles health and fitness information. We do not sell it, we do not use it for advertising, and we ask your permission before it is sent to our AI providers. Our separate Consumer Health Data Privacy Policy gives more detail on health data.
2. What we collect
Information you give us
| Category | What it includes |
|---|---|
| Account | Name, email address, password, date of birth. Google's Firebase Authentication handles your password. We never see or store it in readable form. |
| Athlete profile | Height, weight, sex, sport, position, other sports you play, competition level, fitness level, training days per week, daily practice hours, nutrition goal, optional goal weight, in-season status, game and practice schedule, season end date, equipment and training space |
| Daily check-ins | Soreness, energy, stress, life stress, hydration, hours slept, late caffeine, travel days. Users 21 and older are also asked how many alcoholic drinks they had. |
| Pain and injury log | Body part, type of discomfort (soreness, ache, stiffness, sharp pain), severity from 1 to 5, and the date it resolved |
| Training | Programs, weekly plans, completed workouts, sets, reps, weights, personal records, cardio distance, pace and duration, post-workout check-ins (effort, energy, soreness), heart-rate recovery results, performance benchmarks, readiness score history |
| Nutrition | Meal descriptions, scanned barcodes, calorie and macro estimates, daily nutrition grades, weight history |
| AI coach | Your chat messages and the "coach memories" you write about yourself |
| Messages to us | Anything you send to our support or privacy email, or submit through our feedback form |
Apple Health (only if you connect it)
Connecting Apple Health is optional. If you connect it, GrindSplit reads these data types from your iPhone and Apple Watch:
- Heart rate, resting heart rate, walking heart rate, heart rate variability (HRV)
- VO2 max, blood oxygen, respiratory rate, wrist temperature (where available)
- Steps, walking and running distance, walking asymmetry, exercise time, stand time
- Active energy and basal energy
- Body weight and body fat percentage
- Sleep analysis
- Workouts
GrindSplit also writes your completed workouts to Apple Health.
Apple Health data is read on your device. Values derived from it, such as HRV, resting heart rate and sleep, are used to calculate your readiness score, may be sent to our AI providers with your permission (section 4), and some summaries are saved to your account.
You can turn off access at any time in iOS Settings → Health → Data Access & Devices → GrindSplit.
Camera, photos and music
- Meal photos. A photo you take or choose is sent once for AI analysis and then discarded. We do not store it.
- Form-check videos. Videos of your lifts are analyzed on your phone using Apple's on-device pose tracking. The video never leaves your device. Only text results, such as "knees caved on 2 of 5 reps," are sent to the AI.
- Apple Music. We access your music library only to show and control what is playing during a workout. That information never leaves your device.
Information collected automatically
| Category | What it includes |
|---|---|
| Usage analytics | App events such as workout started or completed, meal logged, check-in saved, program created and coach message sent. These are counts and flags, never the content. Also screen views, app opens, app version, device type and operating system, linked to your user ID. |
| AI usage data | Model name, token counts, response time and errors. No prompt or response text. |
| Crash and diagnostic data | Crash reports, device model, operating system version and app version, linked to your user ID |
| Security data | Request counters per account, used to limit abuse |
| Server logs | Your user ID and the type of event for AI requests, rate limits and account deletions |
Your IP address is visible to any server your device connects to. Google's systems log IP addresses for a short time for security. We do not store IP addresses in our analytics and we do not use them to work out where you are.
What we do not collect
We do not collect your precise or approximate location, your contacts, microphone audio, your browsing history, advertising identifiers (IDFA), or payment card details. We do not track you across other companies' apps or websites.
3. How we use it
We use your information only to run and improve GrindSplit.
| Purpose | Information used |
|---|---|
| Build and adjust your training programs and nutrition targets | Athlete profile, training, nutrition, check-ins, pain and injury log, Apple Health data |
| Calculate your readiness score | Apple Health data and daily check-ins |
| Power AI coaching, meal analysis and form feedback | The information listed in section 4 |
| Sync your data across your devices and show widgets and Apple Watch data | Account, training, nutrition, readiness |
| Understand how the app is used so we can improve it | Usage analytics and AI usage data. Never the content of your messages or your health data. |
| Fix crashes, keep the service secure and prevent abuse | Crash and diagnostic data, security data, server logs |
| Send account emails such as sign-in links and password resets | Email address |
| Answer your questions and requests | Messages you send us |
How readiness works. Your readiness score is an estimate of how prepared your body is to train today. It combines recent Apple Health measurements, such as heart rate variability, resting heart rate and sleep, with your check-in answers, such as soreness, energy and stress, and compares them with your own recent baseline. It is training guidance only. It is not a medical measurement or a diagnosis.
What we never do. We do not sell your information. We do not show ads. We do not use your health data for advertising, marketing or data mining.
4. AI processing
GrindSplit's AI features are powered by Claude, a model made by Anthropic, PBC, and by models made by OpenAI, L.L.C. We ask for your explicit permission before any of your information is sent to either provider.
Features that use AI: training program and weekly plan generation, coach chat, meal photo and text estimates, form-check feedback, and nutrition grades and suggestions.
Which provider handles which feature:
- Coach chat currently runs on OpenAI's models. If OpenAI's service is unavailable, that message is automatically answered by Anthropic's Claude instead, so the coach keeps working.
- Training program and weekly plan generation, meal photo and text estimates, form-check feedback, and nutrition grades and suggestions run on Anthropic's Claude.
We may change which provider handles which feature as the app evolves. This section is updated whenever we do.
What is sent, and to which provider:
- Name, age, sex, height and weight
- Sport, position and competition level
- Goals and goal weight
- Training history and current program
- Apple Health derived metrics: HRV, resting heart rate and sleep
- Readiness score and recovery check-ins
- Nutrition logs
- Coach memories and chat messages — sent to OpenAI, or to Anthropic if OpenAI is unavailable
- Meal photos — sent to Anthropic only
- Form-check text results, never the video — sent to Anthropic only
Requests go through GrindSplit's own server. Your device does not connect to Anthropic or OpenAI directly.
How each provider handles it. Under its commercial terms, Anthropic does not use this data to train its models and states that it deletes API inputs and outputs within 30 days, unless it must keep them longer to enforce its usage policies or comply with the law (Anthropic's retention page). Under its API terms, OpenAI does not use API data to train its models and states that it retains API inputs and outputs for up to 30 days for abuse monitoring, then deletes them, unless it must keep them longer to comply with the law (OpenAI's API data retention policy).
Your choice. You can withdraw your permission at any time in Settings. If you do, AI features stop working: program generation, coach chat, meal analysis, form-check feedback and nutrition suggestions. Logging and tracking continue to work.
Limits of AI. AI output is generated automatically. It can be wrong or incomplete, and no person reviews it before you see it.
Automated decisions. The AI shapes training and nutrition recommendations only. We do not use it to make decisions that have legal or similarly significant effects on you.
5. Health data
We treat the following as health data and give it extra protection:
- Everything read from Apple Health
- Daily check-ins, including stress and alcohol answers
- The pain and injury log
- Weight, goal weight, height and body fat percentage
- Nutrition logs
- Readiness scores and anything else we calculate from the items above
Our commitments:
- We collect health data only with your consent, or as needed to provide a feature you asked for.
- We never sell health data and never use it for advertising or marketing.
- We share it only as needed to provide the service: with Google, which stores it, and with Anthropic and OpenAI, which process it for AI features, and only with your consent.
- Apple Health data is never stored in iCloud.
HIPAA does not apply to GrindSplit. HIPAA covers healthcare providers, health plans and the companies that work for them. GrindSplit is none of these. Your information is protected by this policy, consumer protection law and state privacy laws instead.
See our separate Consumer Health Data Privacy Policy for more detail on health data and your rights over it.
6. Who we share it with
We share information only with the companies that help us run GrindSplit. We do not sell your personal information, and we do not share it for cross-context behavioral advertising, as California law defines "sell" and "share."
| Company | Why | What it receives |
|---|---|---|
| Google (Firebase Authentication, Firestore, Storage, Cloud Functions, Hosting, Crashlytics, Cloud Logging) | Hosting, database, sign-in, crash reporting | Your account and everything stored in it, crash and diagnostic data, server logs. Stored in the United States. |
| Anthropic | AI features | The information listed in section 4, only with your permission |
| OpenAI | AI features (coach chat) | The information listed in section 4, only with your permission |
| PostHog (US cloud) | Product analytics | Your user ID, app events, device and app information, AI usage data. No email address, no IP address, no message or health content. |
| USDA FoodData Central | Food database | Food search terms only, sent from our server with nothing that identifies you |
| Open Food Facts | Food database | Barcode numbers and food search terms only, sent from our server with nothing that identifies you |
| Google Forms | Feedback form | Only what you type, and only if you choose to open and submit the form |
| Apple | Platform | Apple Health data stays on your device under Apple's controls. Apple handles App Store downloads and purchases. |
Google, Anthropic, OpenAI and PostHog act as our service providers under contracts that limit them to processing your information for us and require them to protect it.
Legal requests. We disclose information when the law, a court order or another valid legal process requires it, or when needed to protect someone's safety. We will tell you when we are legally allowed to.
Business transfers. If GrindSplit is merged, sold or reorganized, your information may transfer to the new owner. This policy continues to apply to it. If the new owner wants to use health data in a materially different way, you will be asked for consent first.
Things you share yourself. If you export or share a report from the app, such as a PDF, that copy is outside our control.
7. How long we keep it, and how to delete it
We keep your information until you delete your account, with these limits:
| Information | Kept for |
|---|---|
| Account, profile and programs | Until you delete your account |
| Nutrition and meal logs | The last 30 days |
| Readiness history | The last 365 entries |
| Lift logs and cardio logs | The last 500 entries each |
| Performance benchmarks | The last 500 entries |
| Weight history and discomfort log | The last 200 entries each |
| Workout check-ins and session recaps | The last 100 entries each |
| Archived programs | The last 20 |
| Coach chat history | On your device only. Removed when you sign out or delete your account. |
| Meal photos | Not kept. Sent for analysis, then discarded. |
| Form-check videos | On your device only. Temporary files are cleaned up automatically. |
| Usage analytics (PostHog) | 30 days |
| Crash reports (Crashlytics) | About 90 days (Google's Firebase privacy page) |
| Server logs | About 30 days |
| Data sent to Anthropic or OpenAI | Deleted by whichever provider received it within 30 days (section 4) |
Deleting your account
You can delete your account in the app at any time: Settings → Delete Account. If you cannot get into the app, email privacy@grindsplit.ai from the address on your account.
Deleting your account removes your account, profile, all logs, any uploaded files and your analytics profile from our live systems right away.
For up to 48 hours afterward we keep only your user ID and a timestamp. We use them to remove any analytics events your app sent after deletion. Then they are deleted too.
Google may take up to 180 days to remove deleted data from its backup systems.
8. Your rights
We give every user the rights below, whichever state you live in.
| Right | How to use it |
|---|---|
| Access and get a copy of your information | Use Export Report in the app, or email us for a full copy in a portable format |
| Correct your information | Edit it in the app, or email us for anything you cannot edit |
| Delete your information | Settings → Delete Account, or email us |
| Withdraw consent for AI processing or health data collection | Settings in the app |
| Withdraw Apple Health access | iOS Settings → Health → Data Access & Devices → GrindSplit |
| Know who received your information | Section 6 lists every company. Email us for a list specific to you. |
| Opt out of sale, sharing, targeted advertising and profiling | Nothing to opt out of. We do none of these. |
How to make a request. Email privacy@grindsplit.ai from the email address on your account and tell us what you want. To protect you, we confirm that the request comes from the account holder before acting. We may ask you to confirm details that only the account holder would know.
Response time. We respond within 45 days. If a request is complex we may take up to 45 more days, and we will tell you why.
Authorized agents. Someone you authorize can make a request for you. We will ask for proof of your written permission and may verify your identity directly.
Appeals. If we deny a request, you can appeal by replying to our decision or emailing privacy@grindsplit.ai with the subject "Privacy appeal." We answer appeals within 45 days. If we deny your appeal, you can contact your state Attorney General to submit a complaint.
No retaliation. We will not deny service, charge different prices or provide a lower quality of service because you used these rights.
California "Shine the Light." We do not disclose personal information to third parties for their direct marketing.
9. Children and teens
Under 13. GrindSplit is not for children under 13, and we do not knowingly collect their information. We ask for a date of birth at sign-up and block anyone under 13. If we learn that a child under 13 has an account, we delete the account and its data promptly. Parents who believe their child under 13 has an account can email privacy@grindsplit.ai.
Ages 13 to 17. Teens should use GrindSplit with a parent's or guardian's permission. A parent or guardian can email privacy@grindsplit.ai to review or delete their teen's information. We will take reasonable steps to confirm the relationship first.
Protections for users under 18:
- No advertising and no sale of data, the same as for every user
- Aggressive weight-cut and bulk goals cannot be selected
- Calorie targets never go below a minimum floor
- Goal-weight guidance uses slower rates of change and prompts the user to involve a parent, coach or athletic trainer
- The alcohol question in the daily check-in is not shown
10. Security
We protect your information with encryption in transit, Google-managed encryption at rest, access rules that let each account read only its own data, API keys kept on our server rather than in the app, and rate limiting.
No system is completely secure, and we cannot promise that yours will never be breached. If a breach affects your information, we will notify you, and the regulators the law requires, without unreasonable delay and within the time limits set by law.
11. Other things you should know
Where your data is processed. Your information is stored and processed in the United States.
Our website. grindsplit.ai uses no cookies and no analytics, and loads nothing from third parties. Google, which hosts the site, processes visitors' IP addresses only to deliver it.
Do Not Track and Global Privacy Control. We do not track you across sites or apps, and we do not sell or share personal information. Because of that, these signals do not change how GrindSplit works.
Links to other services. Links to Instagram, Google Forms or other outside services are governed by those companies' own policies.
12. Changes to this policy
We will update this policy when the app or the law changes, and we will change the "Last updated" date above. For material changes, we will notify you in the app or by email before they take effect. Continuing to use GrindSplit after the effective date means you accept the updated policy.
If we want to use health data in a materially different way, we will ask for your consent first.
13. Contact us
Questions, requests or complaints about privacy:
- Email: privacy@grindsplit.ai
- Mail: GrindSplit LLC, 14 Industrial Ave, Mahwah, NJ 07430
- General support: support@grindsplit.ai