Privacy Policy

Effective date: August 17, 2026

Build ("Build", "we", "us", or "our") is a workout-tracking app operated by Sawdust Ventures LLC. This Privacy Policy explains what information the Build app and its companion Apple Watch app collect, how we use it, who we share it with, and the choices you have.

Questions? Email help@usebuild.app.

Information we collect

Account information

When you create an account we collect your email address. If you sign in with Apple or Google, we receive your name and email from that provider (if you use Apple's "Hide My Email," we receive Apple's private relay address instead of your real email). We use a secure authentication provider (Supabase) to manage sign-in. Your profile can also hold a display name, a username, a profile photo, a short fitness goal, and your time zone. During onboarding we ask how you heard about Build and store your answer on your profile.

Workout and fitness data

We store the content you create in the app: workouts, exercises, sets, weights, reps, distances, durations, RPE (effort ratings), set types, routines, folders, notes, personal records, goals, and the dates and times of your sessions. This is the core data that makes the app work and syncs across your devices.

Social content and connections

Build has optional social features. If you use them, we store the connections and content they create:

• Friends. Friend requests you send and receive, and the accepted friendships that result. Friendships are mutual — both people have to agree, or add each other in person by scanning a QR code or opening an invite link. We store the invite links you generate and which account redeemed them.
• Feed activity. Reactions and comments you leave on workouts, and the ones other people leave on yours.
• Direct messages. The text and photos you send in one-to-one conversations, and whether a message has been read.
• Nudges you send to friends, including any short message you attach.
• Challenges and goals. The challenges you create or join, who else is in them, your progress, and anything you post in a challenge's chat thread.
• Shared routines and coaching plans. Routines you send or assign to another user, plans assigned to you, any note attached, and which workouts you ran from a plan.
• Live workouts. While you have a workout in progress and live sharing is on, we store a short-lived record that you are training right now — including elapsed time and set counts — so it can appear in your friends' feeds. It stops being shared when the session ends.
• Blocks and reports. See Content moderation and reports below.

See What other people can see below for the controls over all of this.

Photos you add

If you add a profile photo, a workout photo, a routine cover, a photo on a custom exercise, or a photo in a direct message, that image is stored on our servers (Supabase Storage) and associated with your account so it can sync across your devices. The storage bucket is private, not public — the app reads images through short-lived signed links, and who can see what is enforced on our servers:

• Workout, routine, and custom-exercise photos are readable only by you.
• Your profile photo is readable by any signed-in Build user, because it appears in search results, friend lists, and leaderboards.
• A direct-message photo is readable only by the two people in that conversation, and only for as long as the message exists. Unsending it, or either person blocking the other, ends that access.

You can remove any of these at any time.

Voice recordings (voice set logging)

If you use voice logging, the app records a short audio clip and sends it to our speech-to-text provider (OpenAI) to convert it to text, then uses an AI provider (Anthropic) to turn that text into a logged set. The audio is used only to generate that transcript and is processed in real time; we do not store your voice recordings, and our providers do not use this audio to train their AI models. This feature only runs when you hold the microphone button — the app does not listen in the background. The same applies to voice logging from the Apple Watch app, which records on your wrist and hands the audio to your iPhone to process.

Photos for routine import

If you import a routine from a photo, the image is sent to our AI provider (Anthropic) to extract the routine details. The image is used only to produce that result and is processed in real time; we do not store imported photos, and our provider does not use them to train its AI models.

Automated screening of message photos

To keep the messaging feature safe, every photo sent in a direct message is checked automatically before it can be delivered. The image is sent to our AI provider (Anthropic) and classified for sexual content, violence, hate symbols, and targeted harassment. A photo that fails the check is deleted and never reaches the recipient. Unlike the features above, this one is not optional — a photo cannot be sent without passing it. We keep a record of the outcome of each check (which image was checked, whether it passed, and why) so we can enforce our rules and handle reports; that record is not visible to users. The provider does not use these images to train its AI models.

Purchases & subscriptions

If you subscribe to Build's paid features (Build Pro), the purchase is processed by Apple and managed through our subscription provider (RevenueCat). We receive your subscription status, plan, renewal or expiry dates, and a non-identifying purchase identifier so we can unlock paid features. We never receive or store your payment card details — those stay with Apple. If you cancel and choose to tell us why, we store the reasons you selected and any note you wrote so we can improve the app.

Apple Health data

Apple Health is optional and off until you enable it.

• On iPhone, Build is write-only. With your permission, Build writes your completed workouts (workout type, start and end time, and an estimated active-calorie figure) to Apple Health. The iPhone app does not read any data from Apple Health.
• On Apple Watch, during a workout the watch app reads your live heart rate and active energy from Apple Health so it can show them on your wrist and save them with the workout. These values stay on your device and in Apple Health — Build does not transmit your heart rate or calorie data to our servers or any third party.

We never use Apple Health (HealthKit) data for advertising or marketing, and we never sell it.

Analytics & usage data

We use PostHog (a product-analytics service) to understand how the app is used so we can improve it — for example, how often workouts are started and finished, when voice logging is used, and when the subscription screen is viewed. These events are tied to your account's identifier, a random string that is not your name or email, along with whether you're a paid subscriber, and include basic technical details such as your app version, operating-system version, and device type. We do not use this data to track you across other companies' apps or websites, and there is no advertising identifier (IDFA) involved. Analytics is on by default; you can turn it off any time in Settings → Privacy Settings.

Diagnostics

We use Sentry to collect crash reports and error diagnostics so we can fix bugs. This may include device type, OS version, app version, and technical error details; it is not tied to your name or email, and it does not include your workout content. Crash reporting is on by default; you can turn it off any time in Settings → Privacy Settings.

Advertising & install measurement

If you install Build from one of our ads (for example on Meta/Instagram, TikTok, or Google), we use AppsFlyer, a mobile measurement partner, to understand which ad led to the install and which in-app milestones (such as starting a subscription) followed, so we can measure and improve our advertising. To do this, AppsFlyer may process your device's advertising identifier (IDFA), a limited set of device and event information, and share attributed measurement data with the ad network you came from (such as Meta, TikTok, or Google). We also store the resulting attribution summary (the ad source and campaign) on your profile.

On Apple devices we first ask permission through Apple's App Tracking Transparency prompt. If you decline, we do not access your IDFA and do not track you across other companies' apps and websites — measurement then relies only on Apple's privacy-preserving SKAdNetwork, which does not identify you. You can change this any time in iOS Settings → Privacy & Security → Tracking. We never use your workout content, voice recordings, messages, or Apple Health data for advertising.

Notifications

Build sends two different kinds of notification.

• On-device reminders — rest-timer alerts, workout reminders, unfinished-workout reminders, and goal reminders — are scheduled locally on your phone. Nothing about them is sent to us.
• Push notifications about people — a friend request, a message, a comment, a reaction, a nudge, a shared routine, a challenge update, or a friend finishing a workout — are sent from our servers. To deliver them we store a push token for your device (issued by Expo's push service) alongside your account, and the notification's text passes through Expo's push service and Apple's notification service on its way to your phone.

Every push type has its own switch in Settings → Notifications, and turning one off means the notification is never generated. Your push token is deleted with your account. We do not send marketing pushes.

Emails we send

We use Resend, an email provider, to deliver service-related email — for example a recap near the end of a free trial. Sign-in codes, password resets, and email-change confirmations are sent through our authentication provider. These are transactional, not marketing.

App updates

The app checks for over-the-air updates through Expo's update service, which receives only technical details (such as your app version and platform) needed to deliver the right update.

How we use your information

• To provide and sync the app's features across your devices.
• To operate the social features you choose to use, and to show your content to the people you've shared it with.
• To transcribe voice input and extract routines from photos.
• To screen message photos and keep the community safe, and to review reports.
• To send the notifications and service emails you've enabled.
• To process subscriptions and unlock paid features.
• To understand usage and improve the app.
• To maintain, secure, and improve the app and fix crashes.
• To measure and improve our advertising (only with your permission).
• To respond to your support requests.

We do not sell your personal information. With your permission (via Apple's App Tracking Transparency prompt), we use a measurement partner to attribute app installs and key events to the ads that drove them, as described in Advertising & install measurement above; if you decline, we do not track you across other companies' apps or websites. We never use your workout content, voice recordings, messages, or Apple Health data for advertising.

What other people can see

Nothing you log is public. Build has no public profiles and no global feed — your content is visible to you, and to accepted friends only to the extent you allow.

Your display name, username, and profile photo are visible to other signed-in users who search for you, so they can find the right person to add. When someone who isn't your friend yet opens your profile from search, they also see when you joined and how many friends you have in common — including the names of up to three of them — so they can tell they've found the right person. Everything else is governed by per-category switches in Settings → Privacy Settings → Sharing: workouts and sets, records and top lifts, muscles and stats, live workouts, workout notes, and workouts run from a coach's plan. These are enforced on our servers, so turning one off removes that data from your friends' view rather than just hiding it in the app. Friends who aren't sharing a category are simply omitted from the relevant screens.

Shared links. If you share a workout, routine, or folder, we generate a link that lets anyone holding it view that content without needing a Build account. That link is a snapshot and it is permanent: it does not expire, it cannot be revoked, and deleting the original in the app does not take it down. An invite link, which adds someone as a friend, does expire — after 30 days. You control whether to create either one and who you send it to.

Content moderation and reports

If you report a comment, workout, profile, message, or nudge, we store the report, the reason you chose, and a copy of the reported content at the moment you reported it — we have to keep that copy, because content can be deleted before anyone reviews it. Reports are emailed to us so we can act on them, and we may keep records of reports and enforcement actions for as long as needed to apply our Terms. If you block someone, we store that block so we can keep the two of you apart.

Sharing and disclosure

We share data only with the service providers that operate the app on our behalf:

These providers process data under their own privacy and security terms. We may also disclose information if required by law.

Data retention and deletion

We retain your data while your account is active. You can delete your account from within the app: open your profile (tap your name or photo on the Profile tab), scroll to the bottom, and tap Delete Build Account. This permanently removes your workouts, routines, photos, social content, push token, and associated data from our systems. You may also email help@usebuild.app to request deletion.

Deleting your account takes the content you sent other people with it — your messages, comments, and reactions disappear from their side too. Two things can outlive it. A copy someone else now owns stays theirs: a routine they already saved into their own library, and the snapshot behind any share link you created. And if someone reported you, that report and its snapshot can remain for as long as we need it to enforce our Terms, though it no longer identifies your account. Reports you filed yourself are deleted along with your account.

Security

We use industry-standard measures, including encryption in transit, row-level security on our database, private file storage served through short-lived signed links, and secure on-device storage for your sign-in session, to protect your data. No system is perfectly secure, but we work to safeguard your information.

Your choices

• Turn analytics and crash reporting off in Settings → Privacy Settings.
• Choose what friends can see in Settings → Privacy Settings → Sharing.
• Manage blocks in Settings → Privacy Settings → Blocked Accounts.
• Turn off any notification type in Settings → Notifications.
• Change your ad-tracking choice in iOS Settings → Privacy & Security → Tracking.
• Export your workouts as a CSV from Settings → Export Workouts.
• Delete your account, and everything in it, from your profile.

Children's privacy

Build is not directed to children under 13 (or the minimum age in your country), and we do not knowingly collect their data.

International users

Your data may be processed in the United States and other countries where our service providers operate.

Changes to this policy

We may update this policy from time to time. We'll post the new effective date here and, for material changes, notify you in the app.

Contact

Sawdust Ventures LLC — help@usebuild.app