What we keep, and what we don't.

What's stored

By default, Centerline keeps just:

• Your name and email address (from your ScheduleMaster account)
• A record of when you log in
• Your in-app preferences (favorite aircraft, instructor mode toggle, appearance setting, email preferences)

Optional features

These store a little more, and only if you choose to turn them on:

• Connecting with an instructor or student — the connection itself and its sharing settings, plus a copy of the upcoming reservations and non-financial currency (for example medical and flight-review expiration dates) you choose to share, so the other person can see it in the app. A pending invitation you send by email is stored until it's accepted or expires.
• Rideshare — which of your bookings you've opened to rideshare, any saved rideshare searches and alert settings you create, and — only if you choose to let riders reach you by phone — your phone number (from your ScheduleMaster contact info). If you don't enable phone contact, your number isn't stored.
• Linking another ScheduleMaster club — encrypted sign-in tokens for that account, so you can switch between clubs without re-entering your password.
• Connecting Google Calendar — encrypted Google access tokens, the connected Google account's email, your calendar selections, and a record linking each lesson you book to the calendar event we create for it (detailed in the Google Calendar section below).

That's the complete list. Anything not on it isn't stored.

What's not stored

Your ScheduleMaster password is never stored. It's used once to sign you in with ScheduleMaster, then forgotten.

Your flight history, billing information, currency status, squawks, scheduled maintenance, and reservation details all live at ScheduleMaster, where they always have. Centerline reads that data on your behalf when you ask for it and doesn't keep a copy — with one exception: if you connect with an instructor or student, the upcoming reservations and currency you choose to share are copied so the other person can see them (listed under “What's stored” above). Nothing is shared until you confirm the connection, and disconnecting your last connection deletes the shared copy.

Who has access

Only the Centerline operator. Your information isn't shared with advertisers, isn't sold, and isn't given to any third party for marketing purposes. A few service providers process specific data on Centerline's behalf, each for a single purpose:

• MailerLite — if you opt in to email updates, your email address is processed here to send you that email, and nothing else.
• Google — if you connect Google Calendar, calendar data is exchanged with Google to power the calendar features described below.
• PostHog — product-analytics data (see Analytics below) is processed here so we can understand how features are used.

Google Calendar

Connecting Google Calendar is optional. Nothing happens until you choose to connect it from Settings, and you grant access through Google's own sign-in screen. When you do, here's exactly what Centerline does, and why:

• Reads your free/busy and event times from the calendar(s) you select — used to subtract your existing commitments from your published teaching hours, so students only see times you're actually open when booking on Centerline.
• Reads your list of calendars — used only so you can choose which calendars to check for conflicts and which one new lessons are written to.
• Creates, updates, and deletes events on the calendar you choose — used only to add lessons booked through Centerline to that calendar, and to keep them in sync if a booking changes or is cancelled.

That's the whole list. Centerline does not sell your Google data, does not share it with anyone, does not use it for advertising, and does not use it for any purpose beyond the calendar features above. Centerline's use of information received from Google APIs adheres to the Google API Services User Data Policy, including the Limited Use requirements.

Read live vs. stored. Your free/busy and event times are read live each time your availability is calculated — Centerline keeps no copy of them. What it does store is an encrypted copy of the access tokens Google issues (so it can read and write on your behalf), the email address of the Google account you connected, your choice of which calendars to read and which to write to, and a small record linking each lesson you booked to the calendar event we created for it.

Disconnecting.You can disconnect Google Calendar anytime in Settings. That deletes the stored tokens and revokes Centerline's access at Google, so no further reading or writing is possible. The booking-to-event links may remain as internal bookkeeping, but they hold only identifiers — no calendar contents — and are inert once access is revoked.

Analytics

Centerline uses PostHog, a product-analytics service, to understand which features get used so the app can be improved. It's hosted in the United States and proxied through Centerline's own domain.

What's captured is deliberately minimal: page views and feature events (for example, that a reservation was created or a calendar was connected), tied to your ScheduleMaster user ID. The only profile detail attached is your club's organization ID — not your name, not your email, not your display name. Centerline also records session replays to diagnose interface problems; every form field is masked, and personal details like names are masked on the screens that show them.

This data is used only to understand and improve Centerline. It is never sold.

Email preferences

The first time you use Centerline, we ask whether you'd like occasional email updates — usually about new features, sometimes asking for feedback. It's your choice, and you're not signed up unless you say yes. Whatever you pick, you can change it anytime in your account settings, or by replying to any email from Centerline asking to be removed.

Delete my data

Email contact@oncenterline.app and your record will be removed within a day. This deletes your name, email, login history, stored preferences, any instructor/student connections and the reservations or currency shared through them, any rideshare settings and a phone number you shared for rideshare, any linked-club sign-in tokens, and any stored Google Calendar tokens. It does not affect your ScheduleMaster account, which is separate and continues to work as normal.

Cookies

Centerline uses an encrypted session cookie to keep you signed in between visits — it contains your authenticated session token and nothing else. The product analytics described above (PostHog) also set a first-party cookie to recognize your browser between visits. There are no third-party advertising cookies, and nothing is used to track you across other websites.

Changes to this policy

This page is the current version — the “Last updated” date above reflects the latest changes, so check back here from time to time. If we ever make a change that materially expands how we use information we've already collected about you, we'll notify active users directly rather than relying on this page alone.

Questions

Email contact@oncenterline.app. Real human, will get back to you.