NumMemorize vs BUTURAKU

NumMemorize quizzes you on the digits of well-known constants (such as π, e, √2), and will help you memorize additional digits. This app is a must-have for math and science students, and those wishing to impress teachers, friends and family, or fellow nerds! What party won't be livened up with a 20 digit recall of ϕ (the Golden ratio)? Imagine walking up to the blackboard and writing out √2 to 30, 40, or more digits! Say you're being hustled at a game of pool. Easy, bet your opponent, double or nothing, that you can recount pi to 30, no, even better, 50 digits. Let those other kids fill their heads with useless sports stats. These numbers are timeless and universal! Who knows who you'll impress - armed with this knowledge, you'll probably marry a smarter and better looking spouse, have a better job and live happily ever after! NEW! Now enter your own numbers! You can enter any numbers you'd like: drivers license, card numbers, phone numbers and your own favorite constants and values. Go ahead, enter 99! NEW! You can now just speak your number instead of tapping it in! NumMemorize makes it easy to memorize any number! (99! is 933262154439441526816992388562667004907159682643816214685929638952175999932299156089414639761565182862536979208272237582511852109168640000000000000000000000)

BUTURAKU is a physics simulation app that lets you explore physical phenomena through real-time animations. Understand physics laws intuitively with beautiful visuals. Freely adjust parameters with sliders and observe how physical phenomena change in real time. 12 Simulations: [Translational motion] - Free Fall: Observe the effects of gravity and air resistance. Tap to add balls, swipe to throw them. - Projectile: Adjust launch angle, initial speed, and air resistance to observe parabolic motion. - Inclined Plane: Motion on a surface with friction. Experience sliding conditions by changing angle and friction coefficient. - Brachistochrone: Race three balls down line, arc, and cycloid tracks under gravity. Bernoulli's classic 1696 problem - the cycloid wins. - Energy Conservation: A ball rolls along a roller-coaster track while kinetic and potential energy swap places. Turn on friction to see mechanical energy dissipate into heat. - Collision: 2D collisions based on conservation of momentum and kinetic energy. Momentum vector display available. [Oscillation and periodic motion] - Pendulum: Nonlinear pendulum with high-precision RK4 integration. Drag to set the angle. - Double Pendulum: Coupled pendulums producing chaotic motion. Lagrangian mechanics + RK4. - Coupled Pendulum: Two pendulums joined by a spring exchange energy periodically — the classic beat phenomenon. - Spring: Simple harmonic motion with Hooke's law. Adjust spring constant, damping, and mass. - Circular Motion: Uniform circular motion with centripetal force visualization (F = mω²r). Adjust radius, angular velocity, and mass. [Waves] - Wave: Tap to place wave sources and observe interference patterns. 2D wave equation solved numerically with finite differences. [Features] - Real-time physics simulation - Intuitive touch controls - Freely adjustable parameters via sliders - Physics explanations for each simulation - Dark / Light theme support - Japanese and English language support