Terms of Use

Nabla provides educational explanations and practice. It does not guarantee grades, exam results, admission outcomes, or professional qualifications. Always verify work when accuracy is critical.

You may use Nabla for personal, non-commercial learning. Do not misuse the app, interfere with its operation, reverse engineer protected portions where prohibited by law, or reproduce and redistribute its content as a competing product.

Nabla offers a free tier and an optional paid subscription called Nabla Pro. The free tier includes the opening unit of every course. Nabla Pro unlocks the remaining units across all courses, removes the hearts limit, opens the full hint ladder, and enables Exam Mode. The specific features included in each tier may change as the app evolves.

Nabla Pro is an auto-renewing subscription. The following terms apply:

• Payment is charged to your Apple App Store or Google Play account at confirmation of purchase.
• The exact price and billing period are shown in the app before you purchase, in your local currency.
• The subscription renews automatically at the end of each period unless you cancel it at least 24 hours before the current period ends.
• Your account is charged for renewal within 24 hours prior to the end of the current period.
• If a free trial is offered, any unused portion of the trial is forfeited when you purchase a subscription.

You can cancel at any time from your store account settings — on iOS via Settings → your name → Subscriptions, and on Android via the Google Play app under Payments & subscriptions. Cancelling stops future renewals; you keep access until the end of the period you already paid for. Uninstalling the app does not cancel your subscription.

Purchases are processed by Apple or Google, so refunds are handled by them under their own policies, not by Nabla. Where local consumer law gives you a right to withdraw or a refund, that right applies regardless of this section.

Prices may change. If the price of your subscription increases, the store will notify you and, where required, ask you to consent before the new price applies. You may cancel instead of accepting.

If you reinstall Nabla or move to a new device using the same store account, use the “Restore” option on the Nabla Pro screen to reactivate your subscription.

Nabla contains no advertising. If advertising is ever introduced, these terms and the relevant store disclosures will be updated before release.

We work to keep lessons accurate and the app available, but content may contain errors and features may change, be interrupted, or be removed. Beta and testing releases may be less stable than production releases. If you find a mathematical error, please report it — see the support page.

Nabla’s branding, Del mascot, interface, lesson presentation, and original content are owned by their respective rights holders. Third-party open-source software remains subject to its own licenses.

To the maximum extent permitted by law, Nabla is provided “as is” without warranties. Nabla’s creators are not liable for indirect, incidental, or consequential losses resulting from use of the app. Nothing in these terms limits liability that cannot be limited under applicable law, including your statutory consumer rights.

These terms may be updated as Nabla evolves. Continued use after an update means you accept the revised terms.

Questions can be sent to hamzacakmak833@gmail.com or submitted through the Nabla support page.