Geometry & Formula Calculator vs Perfboard Lab

Formula is a teaching-style geometry and math calculator that shows its work — and it's free for a limited time. Every result walks you through the formula, the substitution, the intermediate step, and the final answer — the same way a teacher writes it on the board. Built for students, parents helping with homework, and anyone who'd rather understand the answer than just see it. WHAT YOU CAN CALCULATE Shapes — 17 shapes across 2D and 3D: • 2D: Circle, Square, Rectangle, Triangle, Right Triangle, Trapezoid, Parallelogram, Regular Polygon, Ellipse • 3D: Cube, Rectangular Prism, Sphere, Cylinder, Cone, Square Pyramid, Triangular Prism, Triangular Pyramid Get perimeter, area, surface area, volume, diagonal, slant height — whichever applies. Many shapes work in any direction: enter the area, get the side. Unit Converter — 12 categories: Length, Mass, Area, Volume, Capacity (cooking: tsp, tbsp, cups, mL, L…), Temperature, Time, Speed, Pressure, Energy, Power, Angle. Every conversion shows the factor and the multiplication, and results list the other measurement system first — metric to imperial or imperial to metric — with the closest-sized units at the top. Physics Formulas — 10 staples: Ohm's Law, Electric Power, Newton's Second Law, Work, Pressure, Distance/Speed/Time, Wave Speed, Density, Concentration, Pythagorean Theorem. Enter any two of the three values and the third is solved for you, with full show-work. A ×10ⁿ key handles scientific notation, so values like 3 × 10⁸ m/s or 6 × 10⁻⁷ m are easy to enter and read. Coordinate Geometry — four operations: Distance, Midpoint, Line Equation from two points, and Line Equation from a slope and a point. Each plots your points on an auto-scaled coordinate plane. DESIGNED FOR LEARNING • Show-work on every result: formula → substitution → step → answer • Share your work: send the full worked solution to a classmate or paste it into your homework. Touch and hold any result to copy it. • Custom keypad with π, ±, ×10ⁿ, and a clear key in the same place on every screen • Visual diagrams that change to fit your input • Multi-field shapes fill in what they can work out • Help on every tab — tap "?" to see what each screen needs and what you get back • Remembers your last tab and units between launches • Universal: iPhone and iPad FREE FOR A LIMITED TIME — NO ADS, NO TRACKING, NO ACCOUNTS No subscriptions, no in-app purchases, no analytics, no third-party SDKs. The app collects no data. From the maker of Fraction Calculator with Work.

Understand electronics by trying it out: Perfboard Lab turns your iPhone, iPad or Mac with Apple silicon into an electronics lab. Build a circuit and switch on the power. Right away you see what happens: LEDs light up, buzzers beep, motors turn and hum. And if your maths was off: it smokes, it sparks and the part burns out – without any real damage. SEE WHAT HAPPENS, INSTANTLY • Every change is computed instantly with real physics • Overloaded parts smoke in four levels until they burn out • The analysis explains in plain words what is wrong: an LED the wrong way round, a missing series resistor, a short circuit, an open circuit MEASURE LIKE IN A REAL LAB • Multimeter: voltage, current and power at every part • Oscilloscope: voltage and current over time OVER 20 REAL PARTS • DC voltage source, AC source, current source and breadboard power supply • Resistors, potentiometers, ceramic and electrolytic capacitors, inductors, switches • Diodes and Zener diodes, NPN and PNP transistors, N- and P-channel MOSFETs, relays, op-amps, voltage regulators and Timer NE555 • LEDs in six colours, an incandescent lamp, a buzzer with a real tone and a motor whose hum matches its turning • Real characteristics as in a parts catalogue, each with a short explanation JUST LIKE ON THE WORKBENCH • Draw wires with the pen – straight wires with bends and branches • Perfboard, with Perfboard Lab Pro also stripboard with cuttable strips and breadboard as used with Arduino • Copy parts with all their values; text labels annotate your circuit • Real 2.54 mm grid: what fits in the app fits on the real board • Bill of materials with every part and the length of every wire • With Perfboard Lab Pro you see your circuit in the 3D view: real parts on the board that you turn, tilt and measure PERFECT FOR SCHOOL AND CLASS • A guided tutorial builds your first circuit with you • AI-assisted tasks and explanations in Perfboard Lab Pro: tasks that suit your level, explanations step by step on the board. • Lots of ready-made examples: from an LED with a series resistor to logic circuits, transistors and op-amps • The interactive formula collection adapts to your circuit: with the power on, every worked example calculates with the measured values of your parts and shows where each number comes from. • Teachers pass their default settings on to the whole class as a file FOR EVERYONE • For iPhone, iPad and Macs with Apple silicon • In many languages and usable with VoiceOver and Voice Control • No ads, no tracking FREE The perfboard with almost all parts and their examples, text labels, the instruments and the simulation are free. A circuit can have up to 7 parts. Your circuit is kept automatically. PERFBOARD LAB PRO With “Perfboard Lab Pro” you save as many circuits as you like and keep working on the same circuit on iPhone, iPad and Mac. You export them as PDF with a bill of materials and share them with others. Plus circuits with more than 7 parts, op-amp, voltage regulator, Timer NE555, motor, Zener diode and current source with their examples, the stripboard and the breadboard with their examples, AI-assisted tasks and explanations, and the 3D view. • Try it free for 3 days, then a weekly subscription. The App Store shows the price in your currency before you buy. • The subscription renews automatically every week unless it is cancelled at least 24 hours before the end of the period. Payment is charged to your Apple Account. You can cancel at any time in your Apple Account settings under “Subscriptions”. • Terms of use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ • Privacy policy: https://pascalschroeer.github.io/PerfboardLab_PrivacyPolicy/ Legal notice: https://pascalschroeer.github.io/PerfboardLab_PrivacyPolicy/#legal-notice