Frequently Asked Questions

Signing in keeps your credits attached to you, not your device. It also prevents the free allowance from being abused, which keeps it available for genuine users.

Very. redmarker reads both printed and handwritten maths with high accuracy, and shows a confidence score for every read so you can see exactly how certain it is. If anything looks off, a quick tap lets you correct it on the spot.

Your photos never live on our servers. When you scan a worksheet, the image is sent securely to OpenAI's OCR service to read the maths directly from your device. OpenAI doesn't use your images for training, and everything else stays on your device only. We only share what's necessary to make the marking work. Nothing more.

redmarker requires an internet connection to process worksheets with OCR. However, once worksheets are processed, you can view results, track progress, and organise worksheets offline. The app also includes a background processing queue, so worksheets captured while offline will be processed automatically when you reconnect to the internet.

redmarker works on iOS 13.0 or later and Android 8.0 (API level 26) or later. The app is optimised for modern devices and takes advantage of the latest mobile technologies for the best performance and accuracy.

Yes, you can export your worksheet data from the app. Use the export option in Settings to back up your data. Export and deletion features are available to give you full control over your information.

When you exceed your monthly free allowance, you can buy worksheet credit packs in the app (Essentials Pack: 50 credits, Value Pack: 200 credits). Credits are used automatically. Purchased credits expire after 1 year of account inactivity. Sign in at least once a year to keep your account active. View credit packs →

redmarker includes a free tier with 10 credits per month for individual tutor accounts; your allowance resets each month and unused credits don't roll over. Tutoring centres and maths programmes can book a demo for institutional pricing with higher volume. See full pricing →

No. Every update, new feature, and improvement is included. Nothing extra, ever. Just keep the app and you'll get everything as it arrives.

Yes. If something isn't working, reach out directly through the Settings screen and we'll get it sorted. We're a small team and take every support request personally.

Yes. redmarker already works with a wide range of printed and handwritten worksheet styles, and we're continuously adding more. If there's a format it doesn't handle yet, let us know. Any updates are included at no extra cost.

No. redmarker is a maths worksheet marking app, not a worksheet library like math-drills.com or K5 Learning. You use your own maths worksheets or maths drill sheets (including Kumon-style practice). Photograph the completed sheet and redmarker checks the answers in seconds.