Privacy policy

Overview

CPO Certify is a study app for the AOA Certified Paraoptometric (CPO) exam, and CPOA Certify is a study app for the AOA Certified Paraoptometric Assistant (CPOA) exam. Both are published by DIN Tech Labs ("we," "us," "our") and are built the same way. Fax Sorter, also published by DIN Tech Labs, is a Windows program that sorts and files faxes in an office. This policy explains what happens — and, more importantly, what does not happen — to your information when you use any of them. It applies to each app on every platform where it is available (iOS, Android, and web for the study apps; Windows for Fax Sorter). Where this policy says “the apps” without more detail, it means the two study apps; Fax Sorter has its own section below. CPO Certify and CPOA Certify are free to download, with an optional subscription: individuals can subscribe through the Apple App Store or Google Play, and practices can buy seat packs for their staff on this website. A subscription sends nothing to us; the seat-pack route is what lets us hold the small amount of data described in the sections on seat codes and practice purchases. The section on this website, practice purchases and the beta sign-up, below, covers dintechlabs.com.

What the study apps do not collect

Through the study apps, we do not collect or have access to any of the following:

• Your name, email address, phone number, or other contact information (the apps never ask for them)
• Account credentials — the apps have no sign-up or login
• Location data
• Advertising IDs, or analytics and usage data
• Your payment card or billing details — subscriptions are handled by Apple or Google, and seat packs by Stripe on our website
• Your answers, scores, or study progress
• Photos, contacts, or any other device data

Neither app contains analytics SDKs, crash-reporting services that transmit data off-device, or advertising networks. The one identifier either app can send us is the random install ID described in the next section, and only if you enter a seat code.

Seat codes in CPO Certify and CPOA Certify

A practice can buy seats for its staff on this website. Each seat is a code that looks like CPO-XXXX-XXXX (for CPO Certify) or CPOA-XXXX-XXXX (for CPOA Certify). Entering a code in the app is the one thing that makes it talk to our server.

• What the app sends. The code, and an install ID: a random string the app makes for itself. It is not your name, your phone number, your advertising ID, or an ID taken from your phone’s operating system. The app sends the same two things again about once a week to confirm your access is still active.
• What we store. The code, its status, the install ID, the date the code was first entered, the date access ends, and how many times the code has been moved to a new device. We do not store your name, your email address, or anything about your studying.
• Why. To confirm the code is real, to start your six months of access when you first enter it, to let you move the code to a new phone or after a reinstall, to switch off a code that was refunded, and to stop one code being shared among many people.
• What the buyer can see. The practice that bought the code can open a private order page that shows, for each code, whether it is unused, redeemed or expired, and when access ends. It does not show your install ID or anything about your studying.
• Network information. Our hosting provider, Cloudflare, processes network information such as your IP address to deliver the request. We use it to limit repeated attempts, so that codes cannot be guessed.

Subscriptions bought in the app

Both apps are free to download. A free preview, the diagnostic pre-test and one lesson per domain, works without a subscription, and a subscription is optional. Individual CPO Certify and CPOA Certify plans are sold and billed by Apple (App Store) or Google (Google Play), under their terms and privacy policies. We do not receive your payment card or billing details. The apps ask the App Store or Google Play directly whether a subscription is active. Nothing about a purchase is sent to DIN Tech Labs, and there is no account or sign-in. You manage or cancel a subscription in your App Store or Google Play account settings.

Information stored on your device

To function as study tools, the apps save the following data locally on your device only, using standard on-device storage (AsyncStorage):

• Your quiz and mock-exam answers and scores
• Study progress, module completion, where you left off in each lesson, and your study streak
• Flashcard review scheduling (spaced repetition)
• Flagged/missed question lists
• The YouTube links you choose to pin to modules
• App settings and preferences (e.g., your chosen pass-probability target and light or dark mode)
• A count of how many times the app has asked you to rate it, and when, so that it does not ask too often

None of this data is sent to us, to any server, or to any third party by the apps. We have no way to see it, and we cannot recover it if you lose your device — that’s by design. If you back up your device, your phone’s own backup (for example iCloud or Google backup) may include app data; that backup is between you and the device maker, and we never receive it.

If you have entered a seat code, the code, the date your access ends and the app’s random install ID are kept in your phone’s secure storage instead (the iPhone Keychain, or the Android Keystore), not in ordinary on-device storage. They are kept for this phone only and are not restored from a backup onto another phone.

Study reminders

Both apps offer optional daily study reminders, which are off until you turn them on, and your phone’s own permission prompt appears first. They are local notifications that your phone schedules and shows at the time you pick, so nothing is sent from a server, and the apps do not use push notifications and never request a push token.

Apple Watch app

Both study apps include a companion Apple Watch app for reviewing flashcards. It adds no collection. It talks only to the paired iPhone app, over Apple’s on-device WatchConnectivity link, and makes no network requests of its own. Flashcard reviews you make on the watch are sent back to the iPhone app and counted there, and the watch keeps a few small settings on the watch itself. Nothing about the watch is sent to DIN Tech Labs or anyone else, and nothing from it leaves your devices. The watch app is part of the optional subscription (or a seat code); without one it shows a locked screen and no cards.

Third-party services

Neither app includes third-party analytics, advertising, or tracking code of its own. The one third-party service you can choose to use is YouTube. Each app links out to YouTube search results for supplementary video content, and lets you optionally pin a YouTube link to a module. On iOS and Android, a pinned video plays inside the app, in YouTube’s own embedded player. When you play a video this way, your device connects to YouTube (Google), which may collect information such as your IP address and how you interact with the video. That is governed by YouTube/Google’s own privacy policy, not ours, and we never receive any of it. A link you follow from the player or from a video search is handled by YouTube or the site it leads to, under that site’s own policy. Apart from the links you choose to open, the videos you choose to play, your subscription with Apple or Google, and the seat-code steps described above, the apps make no outbound network requests involving your data.

Fax Sorter

Fax Sorter is a Windows program that you install on your own computer. It reads the fax PDFs you point it at, from a folder, from your own classic Outlook, or from an email account you give it, sorts and renames them, and files them in folders on your computer or network. It keeps a log of what it did and, if you turn the AI on and ask for one, a short summary of a fax. That is why this section works differently from the study apps above.

• We do not receive your faxes. The faxes, the patient names read from them, the log and any summaries stay on your computer and network. Fax Sorter has no analytics, no crash reports and no usage data, and it sends nothing about your faxes, your patients or your practice to us or to anyone else. Its only network connections of its own are the ones described below.
• Reading faxes from an email account. If you choose this, Fax Sorter connects from your PC to your email provider (for example Google or Microsoft) over an encrypted connection, reads the fax emails there, and moves each email to a folder once its faxes are filed. The password is saved on your PC, encrypted by Windows for that one PC. For Microsoft 365, “Sign in with Microsoft” contacts Microsoft’s sign-in service and saves a sign-in token the same way. Your provider’s own privacy policy covers that mailbox. We never see the mailbox, the password or the faxes.
• Looking for updates. About once a day, Fax Sorter downloads one small public file from our website, dintechlabs.com, to see whether a newer version is out. It sends nothing about your PC, your faxes, your practice, the app’s version or your license: the request is the same one any visitor’s browser would make, so our hosting provider (Cloudflare) sees the network address it came from, as it does for any visit to this site. Fax Sorter never installs an update by itself. You can turn the check off in Settings, under Updates.
• The license check. Once you enter a license key, Fax Sorter checks it with Lemon Squeezy, the service that sells and validates our licenses, when you enter it and then about once a day. It sends only the license key, the activation ID and a name made from a hash of your PC’s ID, never faxes, patient information, file names or your practice’s name. Lemon Squeezy’s own privacy policy covers that exchange.
• The optional AI runs on your computer. If you install it, Fax Sorter sends fax text only to the AI engine (Ollama) on the same PC, at the local address set in its settings. It does not send fax content to any cloud service.
• Setup can download other software. If you choose to install the Ollama AI engine and its model, or the Tesseract OCR engine when the setup does not already carry it, your computer connects to those publishers to download them, and their own privacy policies apply. We never see that traffic.
• Web interface logins. The web interface is protected by usernames and passwords that you create. They are stored on your computer, with passwords kept as salted hashes rather than plain text. The web interface is meant for your office network; to reach it from outside, use a VPN.
• Removing it. Uninstall Fax Sorter from Windows Settings. You choose whether its settings are deleted too. Sorted and incoming fax files stay where they are until you delete them.

Fax Sorter handles patient information on your computer. Keeping that computer secure, deciding who can use it, backing up the files, and meeting your own legal duties for patient information (for example under HIPAA in the United States) stay with you and your practice. DIN Tech Labs does not see or store that information.

Practice seat purchases on this website

Practices buy CPO Certify or CPOA Certify seat packs on this website with a one-time payment. This section covers what happens to the information you give us when you do.

• What we ask for. The practice name, a contact name and an email address, entered at checkout.
• What we keep. Those three details, which apps the seats are for, the number of seats, the amount paid, Stripe’s session and payment reference numbers, the date, the status of the order (paid or refunded), and the codes made for it.
• Payment. The payment page is run by Stripe. Your card details go straight to Stripe and we never see them. Stripe’s privacy policy covers what Stripe does with them.
• How we use it. To show and email you the codes, to give you a private link to your order, to handle refunds and support requests, and to keep the tax and accounting records we are required to keep. We do not use it for marketing, and we do not sell or share it.
• The order email and link. We email the codes and a private order link to the address you gave. The link carries a long random token, and anyone who has it can see the codes in that order, so treat it like the codes themselves. The email is sent through Cloudflare’s email service, which processes your address for that purpose.

This website and the beta sign-up

This website does not run analytics, advertising, or tracking scripts. It remembers one preference in your browser, light or dark mode, which stays in your browser and is never sent to us. Like any web host, our hosting provider (Cloudflare) processes technical information such as your IP address to deliver pages and to protect the site from abuse. The same is true of whichever service delivers a file you download from us.

If you request a beta invite, you give us your name, your email address, your platform, and anything else you choose to write, through a Google Form. We use that only to contact you about testing. We do not send newsletters and we do not share it with anyone. Google handles the form responses under its own privacy policy. If you would like your sign-up removed, email support@dintechlabs.com.

Children's privacy

Our apps are intended for adults, whether people studying for a professional certification exam or staff who work in a medical office, and are not directed at children. The study apps do not ask for personal information from anyone, and seat packs on this website are bought by practices, so we do not knowingly collect personal information from children under 13 (or the relevant age in your jurisdiction).

Data security

Your study data is stored locally on your device and is protected by your device's own operating-system security (e.g., device lock, encryption at rest), which we recommend you keep enabled. Seat-code and order records are held in a database hosted by Cloudflare. Connections between the apps, this website and our servers are encrypted in transit, the private order link uses a long random token, and the support tools we use to look up or switch off a code are protected by a secret key. No system is perfectly secure, but that database holds only what is described above: it has no study history and no payment card numbers in it.

Your choices and data deletion

Your study progress is stored only on your device, so there is none of it on our side to delete. You are always in full control locally:

• Use Reset all progress in the app’s Settings, or clear the app’s data or storage from your device’s app settings, to reset your progress
• Uninstall the app to delete your study progress. A seat code and install ID kept in the iPhone Keychain may remain after the app is deleted; to have the install ID removed, email us at the address below

To remove a beta sign-up, correct or delete a practice order, or have the install ID removed from a seat code, email us at the address below. Removing an install ID ends that device’s access to the code, and we can reset the code so a new device can use it. We may need to keep basic order records for tax and accounting purposes, and enough of a code’s record to stop a refunded or used code being redeemed again.

Changes to this policy

If this policy changes — for example, if a future version of an app adds a feature that requires collecting data — we will update this page and revise the "Last updated" date above before that change takes effect.

Contact us

Questions about this policy or the apps can be sent to support@dintechlabs.com.

DIN Tech Labs is a registered trade name of DIN Tech Labs LLC, an Iowa limited liability company.