Comparison of the 10 Most Common Web-Based Interactive Geometry Apps
Below is a clean, comprehensive comparison table with the criteria you requested:
- ✔ Free
- ✔ Open Source
- ✔ Written in JavaScript
- Notes on strengths and limitations
Comparison Table
| # | Application | Free | Open Source | Written in JavaScript | Key Strengths | Limitations |
|---|---|---|---|---|---|---|
| 1 | GeoGebra | ✔ Free | ✔ Partially open source (UI open, CAS engine not) | ✔ JS (mostly) | Industry-standard dynamic geometry; huge library; powerful tools | Some features closed-source; occasional complexity for beginners |
| 2 | Desmos Geometry | ✔ Free | ✘ Closed source | ✔ JS | Very clean UI; easy classroom integration; excellent for transformations | Limited compared to GeoGebra (e.g., fewer construction tools) |
| 3 | PhET Interactives | ✔ Free | ✔ Open source | ✔ JS (rewritten in JS) | High-quality conceptual sims; classroom-tested; beautiful animations | Geometry coverage is more limited than algebra/physics |
| 4 | Mathigon Polypad | ✔ Free | ✔ Open source | ✔ JS | Highly creative canvas; great for tessellations and manipulatives | Not a full proof or construction environment |
| 5 | Khan Academy Geometry | ✔ Free | ✘ Closed source | ✔ JS (proprietary framework) | Strong auto-graded practice; good diagrams and hints | Not a construction or dynamic-geometry tool |
| 6 | Brilliant.org Geometry | ✘ Paid subscription (free trials) | ✘ Closed source | ✔ JS | Beautiful visuals; interactivity in explanations; strong conceptual focus | Requires subscription; not customizable |
| 7 | IXL Geometry | ✘ Paid | ✘ Closed source | ✔ JS | Standards-aligned practice; adaptive difficulty | Subscription required; limited deep interactivity |
| 8 | Gizmos (ExploreLearning) | ✘ Paid (limited free trial) | ✘ Closed source | ✔ JS | Highly polished virtual labs with teacher materials | Subscription needed; not customizable |
| 9 | NCTM Illuminations (archived but active mirrors exist) | ✔ Free | Partially open (older Flash → JS ports vary) | Partially JS | Classic geometry tools (tessellations, transformations) still widely used | Some tools outdated; inconsistent maintenance |
| 10 | Wolfram Demonstrations | ✔ Mostly free online | ✘ Closed source (Wolfram CDF format) | ✘ Uses Wolfram CDF/Mathematica | Large library; advanced geometry; excellent for visualizing theorems | Not JavaScript; requires Wolfram Player; not editable |
Summary Insights
Best fully free + open-source + JavaScript geometry tools
- Mathigon Polypad
- PhET Interactive Simulations
- GeoGebra (partially open)
These are the closest matches to the MicroSim philosophy.
Best for teaching geometric reasoning and construction
- GeoGebra
- Desmos Geometry
Best for conceptual, visual learning
- PhET
- Brilliant.org (paid)
Best for K–12 mastery practice
- Khan Academy
- IXL (paid)
Would you like:
✔ A ranking of these apps by usefulness for a high-school geometry course? ✔ A gap analysis showing what MicroSim types are missing from the current ecosystem? ✔ A feature matrix comparing tool categories (constructions, transformations, proofs, 3D, tessellations, coordinate geometry, etc.)?
Happy to generate more!