No ads, no marketing analytics. ESP Toolbox doesn't use any advertising or marketing-analytics SDKs.
Your work stays on your device. Wells, calculations, hitches, and usage history are stored locally only.
No personal account required. The calculators work fully offline; a one-time, anonymous device check is used only to run the free trial and manage your subscription.
Crash reports help us fix bugs. Sent automatically through Firebase Crashlytics if the app crashes.
ESP Toolbox's calculators are entirely offline. The table below is a complete list of every piece of data the app touches — there is nothing beyond it.
| Data | Where it's entered | Where it's stored |
|---|---|---|
| Well names and saved calculator inputs/results | You type them in | on device |
| Hitch (work period) dates and labels | You type them in | on device |
| Calculator usage (recent, favorites, most used) | Generated as you use the app | on device |
| Feedback message | Settings → Send Feedback | sent to Formspree |
| Reply-to email address | Settings → Send Feedback (optional) | sent to Formspree |
| Device identifier (Android device ID) | Read automatically, once, on first launch | sent to Firebase |
| Subscription purchase token (from Google Play) | Generated by Google Play when you subscribe | sent to Firebase |
| Crash and error reports (device model, OS version, stack trace) | Generated automatically if the app crashes | sent to Firebase Crashlytics |
Data marked on device above never leaves your phone — it exists only to make the app itself work (showing your saved wells, your history, your favorites) and is not visible to us in any form.
The feedback message and optional email address, if you choose to send them, are used solely to read and respond to your question, complaint, or suggestion. We do not use them for marketing, and we do not sell or share them with advertisers.
The device identifier is used only to recognize that a device has already used its one-time free trial, so the trial can't be repeated by reinstalling the app. The subscription purchase token is used only to confirm with Google Play that a subscription is genuinely active. The crash report data is used only to find and fix bugs.
None of this data is used for advertising, profiling, or marketing, and we do not sell it to anyone.
The feedback form is delivered through Formspree, a third-party form-processing service. When you submit feedback, your message and optional email are transmitted to Formspree over an encrypted connection so we can receive and reply to it. Formspree's handling of that data is governed by Formspree's own privacy policy.
ESP Toolbox also uses Firebase (a Google service) for three narrow purposes: recognizing a device that has already used its free trial, confirming an active subscription with Google Play, and collecting crash/error reports (Firebase Crashlytics) so we can fix bugs. Firebase's handling of that data is governed by Google's Firebase privacy and security policy.
No advertising network and no marketing-analytics SDK is integrated into ESP Toolbox.
Locally stored data uses your device's standard app-sandboxed storage and is only accessible to ESP Toolbox itself. It is removed automatically if you uninstall the app, or you can remove it yourself at any time (see below).
The device identifier, purchase token, and crash reports described above are stored on Firebase's servers, encrypted in transit. The device identifier record cannot be modified or deleted through the app once created, by design — this is what prevents the free trial from being repeated by reinstalling the app.
ESP Toolbox is a professional field-engineering tool intended for petroleum and production engineers. It is not directed at children, and we do not knowingly collect information from anyone under 13.
If ESP Toolbox's data practices change, this page will be updated and the "Last updated" date above will reflect the change. Continued use of the app after an update means you accept the revised policy.
Questions about this policy or a request to review/delete data you've sent us can go to the address below.