Principia review
A visual math app with guided problems and a curriculum reaching Calculus II.
Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
Principia is a mathematics learning app for students moving from sixth-grade fractions through university calculus and proofs. Its eight-tier curriculum covers arithmetic, proportions, algebra, geometry, trigonometry, pre-calculus, calculus, and proofs. The teaching approach combines plain-English explanations, animated visualizations, step-by-step guided walkthroughs, and connections between mathematical topics. On-device progress saving and printable study aids support individual study, making the app a fit for solo learners and small study settings.
The free Explorer plan includes Tier 1, Numbers, Fractions & Ratios, and Tier 2, Proportions & Equations, along with guided walkthroughs for free concepts, live visualizations, and progress saved on the device. Principia Pro adds all 8 tiers and 93 concepts, Algebra through Calculus II, every guided walkthrough, printable study aids, and all future content. The published plans show annual billing at $49.99 per year or monthly billing at $6.99 per month. Both Pro options include a 7-day free trial, while the monthly plan can be canceled anytime. Learners who need only foundational topics may find the free tier sufficient; those progressing into advanced mathematics need Pro.
Principia’s strongest distinction is the way it presents mathematics visually and connects ideas across topics. The combination of live visualizations, worked-problem guidance, and explanations before formulas is suited to learners who benefit from seeing how concepts relate rather than relying on formulas alone. The trade-off is platform coverage: distribution is centered on iOS, with macOS listed as compatible while the App Store notes that Mac compatibility is not verified. Support is available by email. Choose Principia for a structured, visual path through advanced mathematics on Apple devices; choose another option if broader platform access or support beyond email is important.
Principia pros and cons
- Where it wins
- Animated visualizations explain concepts before and alongside formulas
- Guided walkthroughs cover worked problems step by step
- Curriculum spans eight tiers from fractions through Calculus II and proofs
- Where it doesn't
- The free Explorer plan covers only the first two tiers
- Available on iOS and macOS rather than a broader range of platforms
- Support is provided through email
Principia fact sheet, pricing and score →
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