Help us reproduce it
Include the app version, iOS or iPadOS version, device model, steps to reproduce, and what you expected to happen. Screenshots are welcome, but never send passwords, payment-card details, or other sensitive information.
Matinformatics support
Scientific Calculator 991EX Support
Find quick answers below or email us with the details of what happened.
Email support01
Common questions
A few quick answers.
Does the app work offline?
Yes. Calculations, settings, and local history work on your device without an internet connection.
Which features are included for free?
Calculate and Complex are available for free. One Lifetime Pro purchase permanently unlocks the ten advanced workspaces.
Where are my calculations stored?
Calculation history stays locally on your device. Matinformatics does not receive or store it.
Do purchases carry over from another app?
No. Purchases are specific to this app and can be restored on devices using the same Apple Account.
Is this an official calculator-manufacturer app?
No. This is an independently developed app and is not affiliated with or endorsed by any calculator manufacturer.
Purchases and billing
Apple processes App Store purchases and payment details. For billing or refund requests, visit Apple’s Report a Problem service.
Your calculations stay private
Entries, results, and calculation history stay on your device and are not sent to Matinformatics. Read the app privacy policy.