Privacy by design

FieldNook Privacy Policy

Effective date: September 16, 2026

This Privacy Policy explains how FieldNook, its public website, optional support requests, and device access grants are handled by Epicalin LLC ("Epicalin," "we," "us," or "our"). Epicalin LLC is the app provider and, where applicable, the controller of personal information described here.

Contact: Epicalin LLC, 1810 N Burning Bush Ln, Mount Prospect, Illinois 60056 1612, United States. Telephone: +1 312 401 4626. Email: support@epicalin.com.

1. Privacy at a glance

FieldNook is designed to work without an account. Your field cards, quest notes, captured moments, photos, videos, voice notes, badges, reflections, settings, and backup exports stay under your control on your device. The app has no advertising, behavioral analytics, tracking, public profile, public feed, or Epicalin operated content sync service. FieldNook does not request location.

A minimal entitlement check sends an app generated random Installation ID with the product name, platform, app version, and build to Epicalin. This permits an authorized administrator to grant or revoke paid capabilities for that installation. Apple or Google processes store transactions and may process device backups under its own terms. Epicalin processes information you deliberately submit through the secure support form. These limited cases are explained below.

Android store access verification also sends Google purchase tokens, product IDs, the Installation ID, app build and a Google Play Integrity proof to Epicalin's billing service. This service checks purchase status with Google. No field notes or media accompany these checks, and Epicalin does not receive payment card details.

2. Scope

This policy applies to the FieldNook iOS and Android apps, fieldnook.app, support requests about FieldNook, and the Epicalin entitlement service used by FieldNook. It does not replace the privacy terms of Apple, Google, Cloudflare, your device backup provider, or a sharing destination you choose.

3. Information stored locally

You may create field cards containing text, selected photos, selected videos, voice notes, dates, pins, favorites, quest associations, completion history, badge progress, and settings. FieldNook stores this content in its private app container. Epicalin does not receive the content, use it for profiling, or make automated decisions about you with it.

Field stations also store your chosen nicknames and return landmarks, observation dates, conditions, notes, manually entered sound counts and listening duration, ground cover sketches, and branch feature observations. These records stay in the same private container and local backups. Station CSV exports go only to the sharing destination you choose. Sound sit uses a timer and manual counters, not the microphone. Field stations do not collect coordinates or transmit observation data to Epicalin.

Photo preparation decodes and reencodes selected image pixels to remove embedded metadata such as location fields. FieldNook does not claim that content shown inside the image can be anonymized. Video and audio files may retain information contained in the recording itself.

4. Permissions

Camera, photo library, video, and microphone access occur only after you choose the corresponding attachment control. Notification permission is requested only after you choose to enable a local reminder. FieldNook does not request precise or approximate location, contacts, advertising identifiers, health data, or background tracking permission.

5. Installation ID and manual access grants

The installed app creates a high entropy random Installation ID beginning with khi_. The identifier is not derived from hardware, an advertising identifier, an Apple or Google account, a store receipt, location, or field card content. On iOS it is stored in the device Keychain using a device bound accessibility class. On Android it is stored outside operating system backup so it is not cloned to another device.

The app sends the Installation ID, product key, platform, app version, and build to Epicalin's entitlement service. The service records the first and most recent check time and any version guarded grant, expiry, revocation, and administrative reason. The app caches the most recent valid result for a bounded offline period. A recorded expiry is enforced locally. Revocation is received on the next successful check. A manual grant does not alter, cancel, or replace an Apple or Google transaction.

Epicalin OS receives only aggregate installation and manual grant counts for each product and a link to the protected administration service. Epicalin OS does not receive individual Installation IDs.

6. Purchases and subscriptions

Apple or Google processes payments through its native store. FieldNook receives provider supplied product information, purchase state, transaction verification, and entitlement status needed to present offers and unlock features. It does not receive payment card details. No field card content accompanies a purchase.

For Android purchase and restore, the native app queries purchases owned through Google Play and obtains a Play Integrity proof. The app sends the proof, purchase tokens and product IDs with its Installation ID, build, environment and a short lived challenge to Epicalin's billing service over HTTPS. The service checks application, license and device integrity verdicts and asks Google for purchase state, actual subscription expiry, acknowledgement and refund information. Google also sends authenticated purchase status notifications that cause another provider check. These checks support access, purchase security and fraud prevention, not advertising or behavioral analytics. Google processes Integrity requests under its own terms. A failed check preserves your saved collection.

Raw purchase tokens, Integrity proofs and provider response bodies are processed in memory and not retained in Epicalin's billing database or application logs. The service stores purchase token digests, product and access state, expiry, verification times, replacement token digest relationships, and short lived challenge and notification replay records. Challenge records use a digest of the Installation ID. Network providers may process IP addresses and ordinary request metadata to deliver and secure these requests. The app stores only the verified access result, not service account credentials or a transferable store receipt.

Apple and Google may provide Epicalin developer console data such as product, storefront, subscription status, proceeds, tax, refunds, and aggregate sales metrics. Store account identity, transaction records, family eligibility, trial eligibility, and payment credentials are processed under the store provider's terms.

7. Optional ratings and reviews

After at least three completed quests and seven days of use, iOS or Android may display its standard store rating interface immediately after a successful quest completion. FieldNook applies its own per version and 120 day local limits, does not ask your sentiment first, offer an incentive, condition access on a rating, or track whether you completed a review. A separate user initiated control can open the public store rating page. A written store review may be public and may be visible to Epicalin through the provider console.

8. Secure support requests and diagnostics

The app can prepare a local draft, then open the secure FieldNook support page. The draft is not placed in the URL or sent automatically. The support page lets you submit a contact request, feature request, issue report, or diagnostics report. It may receive the request type, subject, message, product, platform, app version, build, locale, submission time, and a random request identifier.

Name and email are optional. An email address is required only if you request a response or progress updates. Diagnostics are optional and are shown before submission. Allowed diagnostics are app version, build, operating system version, device model, locale, and limited noncontent error codes. Diagnostics exclude field card text, photos, videos, voice notes, location, advertising identifiers, payment credentials, store receipts, and the Installation ID.

Do not place private field card content, passwords, payment information, identity documents, health information, or other sensitive information in a support message. The secure form uses Cloudflare Turnstile to reduce automated abuse. Nothing is submitted until you complete the form and choose Send securely.

9. Public website data

The FieldNook website does not use advertising pixels, behavioral analytics, or user accounts. Cloudflare hosts and protects the site and may process ordinary request information such as IP address, requested URL, browser or device data, timestamps, and security signals to deliver and secure it. Epicalin may receive limited operational or security information from Cloudflare.

10. Sharing and exports

When you create an image, PDF, text keepsake, or backup export, FieldNook opens the system sharing interface. You choose the destination. A cloud drive, email service, messaging service, printing service, or other destination receives the file under its own terms. Epicalin does not receive an export unless you deliberately send it to Epicalin.

11. Automatic recovery and platform backup

FieldNook keeps the newest three integrity checked recovery snapshots in its private app container and updates them after durable changes. There is no app setting that disables this protection. Eligible private app data may be included in iCloud device backup or Android Auto Backup according to your provider account, device settings, encryption availability, quota, and policies. Epicalin does not operate or decrypt those backups.

12. Information we do not collect through the app

FieldNook does not automatically collect or transmit field card content, chosen media, precise or approximate location, contacts, health information, browsing history, advertising data, or app usage analytics. It does not sell personal information or share it for cross context behavioral advertising. The random Installation ID and Android purchase verification information are described in Sections 5 and 6.

13. Purposes and legal bases

Where law requires a legal basis, entitlement information is processed to perform the app agreement, administer paid and complimentary access, prevent misuse, and maintain reliable access. Support information is processed to take requested steps, provide assistance, resolve problems, evaluate improvements, and maintain necessary business or security records. Optional progress updates are sent because you requested them and may be stopped at any time. Website security data is processed to deliver and protect the service and for our legitimate interest in reliability and abuse prevention.

14. Service providers and disclosure

Limited website, entitlement, support, diagnostics, and response information may be processed by providers that help us host, secure, store, and communicate, including Cloudflare and our business email provider. Authorized Epicalin administrators access individual submissions only through the protected source system. Apple and Google independently process store, device backup, review, and download information. We may disclose limited information when reasonably necessary to comply with law, protect rights or safety, investigate abuse, or complete a corporate transaction subject to appropriate safeguards. We do not provide personal information to data brokers.

15. Retention and deletion

Local content remains until you delete it, clear app storage, restore over it, or uninstall the app. Export copies remain where you placed them. Platform backups follow provider retention controls.

Individual support requests, optional contact details, diagnostics, and response history are scheduled for deletion no later than 365 days after submission unless a shorter request applies or a longer period is reasonably necessary for an active dispute, security investigation, legal hold, or legal obligation. Installation and grant records are ordinarily deleted no later than 365 days after an installation stops checking in or its grant is revoked or expires, subject to dispute, security, accounting, legal hold, and legal obligation exceptions. Privacy minimized aggregate themes have a separate bounded expiry and contain no raw message or customer identity.

Active reviewer grants preserve their installation records until revoked. After revocation, normal installation inactivity retention applies to redemption records. Code digests, scope, consumed quota and code audit records without raw Installation IDs are retained for credential security and replay prevention. The raw code is not retained by the service.

Android billing challenge records are scheduled for deletion one hour after expiry. Purchase observations and notification replay records are scheduled for deletion after 90 days without a check. Bounded hourly cleanup can delay removal when a backlog exists. Replacement token digests and their timestamps remain for replay prevention so an old replaced purchase cannot become active again. These records contain no raw tokens, store account email, field notes or media. Contact support about deletion; security, dispute and legal retention exceptions may apply.

16. Security and international processing

FieldNook relies on private operating system storage, integrity checking, device protections, encrypted HTTPS for limited service calls, and access controlled administration. No system is perfectly secure. Protect your device, store account, and export destinations. Limited website and support information may be processed in the United States and other places where providers operate. Applicable legal safeguards are used where required.

17. Your rights and choices

Depending on where you live, you may have rights to know, access, correct, delete, restrict, object, receive a portable copy, withdraw consent where applicable, or appeal a denied privacy request. You may also complain to a local data protection authority.

Most FieldNook content is controlled directly on your device. For information Epicalin may hold from support or an Installation ID grant, contact support@epicalin.com and include the request reference or Installation ID when available. We may need to verify the request and may retain information where law permits or requires. FieldNook has no sale or targeted advertising system, so there is no sale or advertising opt out to apply.

18. Children, changes, and contact

FieldNook is a general audience application and is not directed to children under 13. Adults should supervise device and outdoor use by children. If you believe a child submitted personal information through support, contact us so we can review and delete it where required.

If a future version changes data handling, we will update this policy and the relevant store disclosures before release. Privacy questions and rights requests may be sent to support@epicalin.com or to Epicalin LLC at the address above.