Beautiful Planimetry vs SectionLab

Geometry doesn’t have to feel impossible. When my daughter first opened her geometry book, she looked at the page — circles, triangles, and lines everywhere — and sighed: “Dad, this makes no sense.” I knew that feeling. So I built a way to make geometry visible. With sliders, motion, and colour, she could see how shapes connect — how an angle changes a triangle, how circles hide perfect relationships, how formulas aren’t just rules but reflections of movement. That small idea became Beautiful Planimetry — an interactive geometry world where math comes alive. Instead of memorising formulas, explore how they work. Move a slider and watch a shape stretch, rotate, or reveal a hidden pattern. Suddenly, geometry isn’t about remembering — it’s about discovering. What you’ll find inside Included for free: - Circle Geometry: basics, inscribed angle, right triangle on diameter, law of sines - Circle Area: circle, sector, segment, ring - Thales’ Theorem: parallel lines crossed by an angle - Angle Bisector: see how angles are perfectly divided - Triangle Basics: triangle types, Pythagoras, law of cosines, inscribed circle in a right triangle, right triangle inscribed in a circle Unlock more with one in-app purchase: - Triangle Area: base × height, two sides + angle, Heron’s formula, equilateral triangle - Quadrilaterals: square, rectangle, parallelogram, rhombus, trapezoid, kite - Regular Polygons: triangle, square, pentagon, hexagon, octagon Why students love it - Visual learning — see shapes change in real time - Instant clarity — connect formulas to the figures they describe - Confidence boost — explore before practicing, so exercises feel easier Who it’s for - Students who want geometry to finally click - Teens tired of memorising without understanding - Parents and tutors who want to make math less stressful Beautiful Planimetry was born from a real story: a dad helping his daughter who struggled with math. What started as a simple app to make functions easier has grown into a family of apps that now includes geometry. Stop memorising. Start understanding. With Beautiful Planimetry, geometry becomes simple, visual, and — yes — beautiful.

SectionLab transforms abstract geometry into a hands-on, visual experience. Perfect for students, teachers, and anyone curious about how 2D relates to 3D. BUILD mode — See 2D become 3D Watch flat shapes transform into solid objects through three different mechanisms: • Rotate: Spin a rectangle into a cylinder, a triangle into a cone, or a semicircle into a sphere • Translate: Extrude a circle upward to form a cylinder, or a square into a cube • Roll: Curl a flat plane into a cylindrical surface Drag the progress slider to control how far the transformation goes, or hit Auto Play for a seamless demonstration. CUT mode — Slice 3D shapes to see inside Choose from five geometric solids (cube, cuboid, cylinder, cone, triangular prism) and cut them with an adjustable slicing plane: • Move the cutting plane up/down and tilt it in any direction • Pull the two halves apart to examine the cross-section in detail • Toggle visibility of each half to focus on either side • Use the Cross-Section Dictionary for instant access to classic cuts (circle, ellipse, triangle, hexagon, and more) Why SectionLab? • Fully interactive 3D — pan, rotate, and zoom with touch gestures • No internet required — all 3D rendering runs locally • Multi-language support: English, 中文, 日本語, 한국어 • iPad-optimized with large touch targets • Clean, distraction-free interface designed for focused learning Perfect for: - Middle school and high school geometry students - Teachers looking for classroom demonstration tools - Self-learners exploring spatial reasoning - Anyone curious about the math behind 3D shapes