Extenup · Board & Batten Calculator

Privacy policy

Effective 4 September 2026

Board & Batten Calculator ("the app") is an offline wall-layout planning application. This Privacy Policy explains the information the app handles and how it is used.

Information you enter

The app handles project information that you choose to enter, including project names and notes, measurement units, wall and treatment dimensions, trim profiles, spacing choices, waste allowance, and keep-clear openings such as doors, windows, outlets, switches, cabinets, or custom obstructions.

This information is used only to save local projects, calculate and display the layouts you request, prepare mark, cut, and material summaries, create a PDF when you choose that action, and create the plain-text mark list when you choose Copy marks.

Local processing and storage

Board & Batten Calculator processes calculations and project information on your device. Projects and settings are kept in the app's private local storage. They are not uploaded to Extenup or a developer-operated server.

The app has no cloud account, synchronization, or developer-operated backup service. Android cloud backup and device-to-device transfer are disabled for the app's private data.

Data collection and sharing

Board & Batten Calculator does not automatically collect, transmit, sell, or disclose personal information, project content, measurements, device identifiers, analytics, diagnostics, advertising data, or usage events to Extenup or third parties.

The app has no account system, advertising, analytics, tracking, attribution, crash-reporting, cloud, billing, or remote-code SDK. It requests no runtime, dangerous, or sensitive Android manifest permission and declares no Internet, network-state, advertising-ID, media-library, or broad-storage access. AndroidX contributes an app-signature receiver-protection permission that does not prompt the user or provide access to user data. Save PDF uses only the scoped document access granted when you select one destination.

Saving a PDF

When you choose Save PDF, the app first renders an integrity-checked pending copy in its private, non-backed-up local storage. It then opens Android's system document picker so that you choose the destination. This private staging copy and its private recovery metadata, including an opaque local project identifier used only to return the outcome to the project that started the save, let the app save the exact report you requested if Android recreates the screen while the picker is open. The staged copy is not exposed through the app's FileProvider and is not uploaded to Extenup or a developer-operated server. A document provider selected by you may store or synchronize the saved PDF under its own terms.

After the document picker returns your selection, the app may temporarily store the selected document's content URI, the opaque local project identifier, the staged PDF's expected byte count and fingerprint, and scoped read/write grant flags in private, non-backed-up app preferences. It asks Android to persist access only to that selected document so that it can finish or recover the save you requested after a process interruption. This destination reference, local routing and integrity metadata, and scoped grant are not sent to Extenup and are not used to access other files.

Canceling the picker creates no destination record or persisted grant and triggers best-effort deletion of the private pending copy. After a confirmed successful save, expiry, cancellation, or a replacement export, the app attempts to clear the relevant picker or transfer record, release any scoped document grant, and delete the private pending copy. A write or verification failure deliberately retains the transfer record and scoped grant for recovery, as well as the staged copy when it has not already been consumed after a verified write, and retries the requested recovery no more than once per cold app start while it remains recoverable. On cold start, the app also attempts to reconcile and release stale or orphaned Save PDF grants.

For crash-safe result delivery, the app records a private, URI-free receipt for a saved, expired, or canceled outcome before terminal cleanup. This receipt contains only the opaque staged token and fingerprint, the opaque local project identifier, and the outcome; it does not contain the selected destination URI or grant flags. It remains until a live app screen consumes the result and the terminal cleanup can be acknowledged. If that cleanup or receipt removal fails, the app retries briefly and again before the next explicit Save PDF action. A nonterminal failure result may be kept only in process memory as the failure outcome and opaque local project identifier until a live screen consumes it or the process ends; the durable retryable transfer record remains authoritative, and a later cold start re-derives the failure when needed. Neither kind of receipt is sent to Extenup.

At app startup, the app makes a best-effort attempt to remove incomplete or pending-save files older than 24 hours. This is a cleanup threshold, not a guaranteed maximum retention period: a staged copy, transfer record, or scoped grant can remain longer until another cleanup opportunity or after cleanup failure. Clearing app storage or uninstalling removes the app's private recovery state, receipts, and access. The PDF saved at your chosen destination remains there until you delete or move it. The app does not send the PDF to Extenup.

Sharing a PDF

When you choose Share PDF, the app creates a unique temporary PDF below its restricted app-private cache/shared-layout-plans directory and opens Android's system share sheet. The share copy is exposed through a non-exported FileProvider, and the receiving app selected by you receives read access to its content URI. The app does not send the PDF to Extenup. Extenup receives it only if you independently choose Extenup as a recipient or attach it to a support message using another app.

At app startup and before creating a later share copy, the app makes a best-effort attempt to delete temporary share directories older than 24 hours. This is a cleanup threshold, not a guaranteed maximum retention period. A temporary copy can remain longer until another cleanup opportunity or if deletion fails. Android may remove cache files sooner, and clearing app storage or uninstalling the app removes its private cache. A receiving app or service may retain its own copy under its own terms and privacy policy.

Copying marks

When you choose Copy marks, the app places the current wall's plain-text layout marks on Android's system clipboard so that you can paste them elsewhere. This is a deliberate user action. The app does not read clipboard content and does not send the copied marks to Extenup.

The system clipboard is outside the app's private storage. Depending on the Android version and device, Android, the keyboard, and other apps permitted by the operating system, including an app in the foreground, may access, preview, or retain clipboard content under their own practices. Clipboard text may remain until Android or the user clears it or another copy replaces it; uninstalling this app does not guarantee removal of clipboard content or copies retained elsewhere.

Retention and deletion

Local projects remain until you confirm their deletion in the app, clear the app's storage, or uninstall the app. Pending-save PDFs, Save PDF recovery records and scoped grants, Save PDF result-delivery receipts, and temporary-share PDFs follow the cleanup behavior described above. Files saved outside the app remain until you delete them from their selected destination. System clipboard content follows the behavior described above. Clearing app storage or uninstalling removes private app data and the app's scoped access but does not remove PDFs saved elsewhere, clipboard content, or copies already provided to or retained by another app.

The app does not send project or personal data to Extenup, so there is no app account or server-side app-data record to retrieve or delete. If you voluntarily contact Extenup, the contact service delivers the message, address, and anything you choose to include; that support correspondence is handled only to answer and maintain the support record and can be deleted on request by emailing the address below.

External actions

The in-app privacy-policy link opens a separate browser and does not attach project information. Android, a keyboard, a clipboard-enabled foreground app, a document provider, a receiving app, or another service you choose may process content you explicitly copy, save, or share under its own terms.

Children's privacy

Board & Batten Calculator is not directed to children under 13. The app does not knowingly collect personal information from children or any other users.

Planning limitation

The app provides layout and material estimates based on information entered by the user. It does not measure a wall, assess structure or utilities, choose fasteners or clearances, or determine manufacturer or code compliance. This product limitation does not change the privacy practices described above.

Changes to this policy

If this Privacy Policy changes, the updated version will be published at the same public location with a revised effective date.

Contact

Board & Batten Calculator is published by Extenup. Privacy questions and requests to delete voluntary support correspondence can be sent to extenup@gmail.com. Email is handled by the user's and Extenup's email providers under their respective terms.