Last updated: September 15, 2026

Alcor was first released under the name Blitzcalc. Same app, same developer, new name.

These Terms of Use ("Terms") govern your use of Alcor (the "app"), published by Lars Haneveld. By downloading or using the app, you agree to these Terms.

Use of the app

Alcor is provided for personal, non-commercial use as a mental-math practice tool. You may use it on any device you own, subject to Apple's Usage Rules in the App Store Terms of Service.

Subscriptions

Alcor offers an optional auto-renewing subscription, Alcor Pro, available as a monthly or a yearly plan, each starting with a 7-day free trial. Pro unlocks:

• the Blitz Exam — a fixed 20-question paper across everything you have practised, scored out of 100 and kept as a history;
• your weekly report — this week measured against last, plus a reminder that names a skill before it fades;
• the Diagnosis — the single mistake behind most of your errors, across every topic;
• Review Sets — a set of skills with a goal and an exam date;
• full Manual Mode — practise any of the app's skills, in any mix;
• unlimited practice — no daily round limit;
• the advanced statistics, including Mistake Lab history.
• Payment is charged to your Apple ID account at confirmation of purchase.
• Subscriptions renew automatically unless auto-renew is turned off at least 24 hours before the end of the current period.
• Your account is charged for renewal within 24 hours before the end of the current period, at the price you agreed to.
• You can manage or cancel your subscription at any time in Settings ▸ [your Apple ID] ▸ Subscriptions.
• Any unused portion of a free trial is forfeited when you buy a subscription.

Free plan limits