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Privacy Policy

Last updated: 25.04.2026

Welcome to SkillTrees

SkillTrees is a fitness and calisthenics app that helps you plan workouts, track progress, and adapt training based on your history, preferences, and feedback. This Privacy Policy explains what personal data we process, why we process it, which services help us run the app, and how you can control your data.

We try to collect only what is needed to provide the service. We do not sell your personal data, we do not use advertising networks, and we do not use your personal data for third-party ad targeting.

Who Is Responsible for Your Data

Controller: SkillTrees, operated as a Switzerland-based sole proprietorship / individual business.

Country: Switzerland

Privacy and support contact: support@skilltrees.net

We are a one-person business and do not publish a private residential address on this website for personal safety and privacy reasons. Please contact us by email for privacy, legal, support, or data requests. If a postal address is legally required for a specific matter, we will provide an appropriate contact method where required by applicable law.

Information We Collect

Data Category Examples Why We Use It
Account data Email address, name, family name, password hash, account status, email verification status To create and secure your account, let you log in, send service emails, and provide support
Authentication and security data Login timestamps, failed login attempts, refresh/session tokens, IP address, device/browser information To protect accounts, prevent abuse and bots, detect suspicious activity, and keep the service reliable
Training profile and preferences Primary sport, workout location/equipment preferences, workout language, selected skills, milestones, saved notes To personalize workouts and make recommendations that fit your goals, equipment, and preferences
Workout and performance data Generated workouts, exercise history, workout logs, sets, reps, times, weights, difficulty feedback, session notes To track progress, adapt training difficulty, avoid repeating unsuitable workouts, and improve future plans
Health, injury, and body measurement data Bodyweight, birth month/year and derived age if provided, gender if provided, body measurements, user-entered pain or injury notes such as “knee pain”, “shoulder pain”, or “lower back pain” To personalize training safely, avoid exercises or body areas you mark as painful, and calculate relevant fitness targets
Family and subscription data Plan type, entitlement status, purchase or subscription status, family group membership/invite state, credit usage To provide paid features, family sharing, restore purchases, enforce fair usage limits, and prevent fraud
Communications Support emails, feedback, optional newsletter consent and unsubscribe state To answer you, send required service emails, and send optional marketing only if you opt in
Local app storage Session state, offline workout logging queue, temporary workout autosave, app version/build data, preferences needed by the app To keep the app usable, support offline/poor-network flows, and avoid losing an active workout
Health and injury notes: We do not ask you to diagnose yourself. If the app asks what hurts, examples might be “knee pain”, “ankle pain”, “shoulder pain”, or “lower back pain”. We use this only to help avoid unsuitable exercises or areas. SkillTrees is not a medical service and does not try to diagnose, treat, or fix injuries.

Legal Bases for Processing

Purpose Legal Basis
Providing accounts, workouts, logging, paid features, family sharing, and support Performance of our contract with you
Processing optional injury, pain, health-related notes, and body data you choose to enter Your explicit action/consent and our need to provide the training personalization you request
Security, abuse prevention, fraud prevention, service reliability, and basic analytics Legitimate interests, balanced against your privacy rights
Payment records, accounting, tax, app-store obligations, and legal requests Legal obligations and legitimate interests
Optional newsletters or promotional emails Your consent, which you can withdraw at any time

AI Workout Generation and Memory

SkillTrees uses AI to generate and improve workouts. The AI is used to create training suggestions and avoid exercises that appear unsuitable based on the information you provide. It is not used to provide medical advice, injury diagnosis, treatment, or rehabilitation plans.

What we send to the AI provider

What we do not intentionally send to the AI provider

We use Google Gemini through a paid API. Based on Google’s API terms for this type of service, prompts and responses are not used by Google to train or personalize Google’s AI models. We may keep prompts, responses, and related generation logs for up to 55 days to debug failures, improve workout quality, prevent abuse, and understand why a generated workout did or did not meet expectations.

Your control: Do not include sensitive information in notes unless you want SkillTrees to use it for workout personalization. You can delete your account at any time from profile settings and you can email support@skilltrees.net to ask what data we hold about you.

Cookies, Storage, and Analytics

Essential cookies and storage

We use essential cookies and local app/browser storage for:

Analytics

Where enabled, we may use privacy-focused, self-hosted analytics to understand general product usage and detect issues. We do not use analytics cookies, advertising cookies, or cross-site tracking. Analytics may include aggregated page or feature usage, browser/operating system type, screen size, referral source, and approximate country. IP addresses are not stored for analytics purposes.

Because device and usage information can sometimes still be personal data under privacy law, we treat it carefully and use it only to improve and secure SkillTrees.

Third-Party Services We Use

Service Purpose Data Involved
RevenueCat Subscription infrastructure, entitlement management, receipt validation, web checkout App user ID/account-linked ID, entitlement status, product identifiers, purchase/subscription events, receipts, selected package, and email for web checkout
Apple App Store / Google Play In-app purchase processing, subscriptions, refunds, purchase restoration Store account/payment processing handled by Apple or Google; SkillTrees receives purchase and subscription status through store receipts and RevenueCat
Google Sign-In / OAuth Optional account login/registration Google account identifier and basic profile details such as email/name, depending on the login flow and scopes
Google Gemini API AI workout generation and personalization Workout constraints, history, notes, AI memory summaries, optional profile details needed for personalization, and user-entered pain/injury notes; we do not intentionally send email, name, birth month, birth year, or authentication credentials
Brevo Email delivery Email address for verification, password reset, account/security emails, and optional newsletter emails if you opt in
YouTube / Google APIs Exercise video search or related exercise media features where used Search terms or exercise-related queries, not account credentials
Self-hosted analytics Product usage understanding and issue detection Aggregated usage events and technical information; no analytics cookies or advertising identifiers

Some providers may process data outside Switzerland, the EU, or the EEA. Where required, we rely on appropriate safeguards such as adequacy decisions, data processing agreements, Swiss/EU Standard Contractual Clauses, or equivalent mechanisms offered by the provider.

Data Security

No online service can guarantee perfect security, but we work to protect your data and limit access to what is necessary to operate SkillTrees.

Emails and Communications

Service emails

We send required service emails such as email verification, password reset, security notices, account notices, billing-related notices, and important policy updates. These are necessary to run the service.

Newsletter

If you opt in to marketing/newsletter emails, we may send training tips, product updates, and articles. You can unsubscribe at any time using the unsubscribe link in the email or by contacting support@skilltrees.net.

Your Rights and Choices

Depending on where you live, you may have rights to:

Account deletion

You can delete your account at any time from profile settings. The deletion flow requires your email and password so we can confirm it is really you. Account deletion is intended to be immediate for your account and core app data, subject to limited backups, logs, legal records, fraud-prevention records, or records that app stores/payment providers must keep.

Data access

We do not currently provide a self-service export button. You can email support@skilltrees.net to ask what data we hold about you or to request a copy, and we will respond as required by applicable law.

How Long We Keep Data

Changes to This Policy

We may update this Privacy Policy when the app, services, providers, or legal requirements change. For significant changes, we will notify users by email or in-app notice where appropriate. The “Last updated” date shows when this page was last changed.

Contact Us

Privacy, support, and legal questions: support@skilltrees.net