Plottron vs Chess Clock

A graphing + scientific calculator. • 2D and 3D graphing Graphs regular functions, parametric relations, and functions in polar/spherical coordinates. • Implicit graphing • Visualization of complex maps w=f(z) featuring domain coloring plots • For 2D functions: Info mode with tangent line and 2nd-order Taylor approximation Scientific calculator features: • User-defined variables and functions • Symbolic derivative (e.g.: D(x, sin(x)) • nCr, nPr, factorial • Complex numbers • Live evaluation (calculate as you type) • Calculation history • Probability density functions: Binomial, Normal (Gaussian), Student’s t • Cumulative probability density functions • Inverse CDF functions: Normal (Gaussian), Student’s t Examples: Implicit graph: cos(X)=sin(Y) Graph a parabola in Regular mode: X^2 Graph a circle in Parametric mode: cos(T);sin(T) Set a variable: X=5 Use a variable: X+4: 9 Define a function: f(X)=X+1 Use a defined function: f(2): 3 Symbolic derivative: D(X,sin(X)): cos(X) Complex magnitude plot in 3D Regular mode: abs(1/cos(X+Yi)) Notes: • Swipe left for settings. • Use semicolon (;) to separate functions in parametric relations. • Swipe down on keypad to show full history. Tap on answer to show keypad again.

The most beautiful chess clock on iPhone. Tempo is a native, drift‑free chess clock built for modern iOS. One‑tap simple for a casual game between friends; tournament‑accurate when it counts. No ads. No clutter. Just a gorgeous clock that keeps honest time. ► FREE, AND FAIR Both players always get an accurate, mute‑able clock — free, forever. Count down to the flag, or switch to Count Up and run each side as a stopwatch. Play, pause, reset. That’s the whole game, and none of it is behind a paywall. ► DRIFT‑FREE PRECISION Most clock apps slowly drift and lose time — fatal in blitz. Tempo derives every reading from the phone’s monotonic clock, so the time is always correct to the millisecond. Tenths of a second kick in automatically under 20s. ► EVERY TIME CONTROL Presets from Bullet to Classical, plus the full competitive spectrum: Fischer increment, Bronstein, Simple Delay, and Hourglass. Build and save your own — including asymmetric handicap times for uneven matchups and coaching. ► SEVEN LIVING CLOCK FACES Not recolors — full renderers, each with its own digits, motion, and time‑trouble behavior: Minimal, LED, Flip split‑flap, Analog with a real falling flag, Nixie tubes, Pixel dot‑matrix, and the gilded Grandmaster (with its own boom‑bap sound). Switch anytime with live previews. ► HANDS‑FREE & ACCESSIBLE Spoken countdowns (“one minute… ten… flag”) and per‑move readback let you play without looking. Pick any voice installed on your phone. A genuine accessibility win — and nobody else in the category ships it. ► LIVE ON YOUR LOCK SCREEN The active clock ticks in the Dynamic Island and on the Lock Screen, so you can follow the game without keeping the app open. ► BUILT TO BE TRUSTED The screen stays awake all game. It auto‑pauses if you leave the app and reconciles the time perfectly. Reset needs a deliberate confirm mid‑game, so a stray tap never wipes your position. ► HAPTIC & SOUND A satisfying thump on every turn, a warning when a side drops low, and an alarm on the flag. Turn any of it off — for free. ► HISTORY & STATS Every finished game is logged: winner, time control, moves, duration — with win splits and averages. Not just for chess: Tempo is a perfect timer for Go, Shogi, Scrabble, backgammon, and debate. —— TEMPO PRO (optional, one‑time unlock) The clock is free. Pro adds all seven faces, the Bronstein/Delay/Hourglass modes, live add/remove‑minutes, unlimited custom controls, and spoken time.