Pi vs SectionLab

Discover π like never before. Pi — Infinite Digits lets you calculate any decimal of the mathematical constant π with absolute precision. Whether you're a student, a mathematician, or simply curious, this app gives you access to the infinite digits of π directly on your iPhone. Two powerful modes: First N digits — Display the first N decimal digits of π, from 1 to 50,000 locally, and beyond via the internet. Nth digit — Find exactly which digit appears at any position in π. What is the 1,000,000th decimal? Find out in milliseconds. Unmatched precision: Pi uses the Chudnovsky algorithm, one of the fastest known methods for computing π, combined with arbitrary-precision arithmetic (BigInt). Every digit is mathematically exact — no floating point approximation, ever. For large numbers: Beyond 50,000 digits, Pi seamlessly connects to Google's pi.delivery API, giving you access to over 100 trillion decimal digits of π. The largest calculation ever made, right in your pocket. Features: Arbitrary precision up to 50,000 digits — fully offline Unlimited digits via internet (Google pi.delivery) Real-time progress bar with elapsed time Calculation history (last 5 results) Copy result to clipboard Export and share your results Clean, intuitive interface No ads, no subscriptions, no data collection Did you know? π (pi) is an irrational number — its decimals never repeat and never end. Mathematicians have computed over 100 trillion digits. Now you can explore them too.

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