xFractal vs SigiCalc

Explore the infinite beauty of fractals with your fingertips. Pinch to zoom, drag to pan, and dive into the endless detail of the Mandelbrot set and its relatives — rendered in real time on your device's GPU. xFractal, first released in 2008, is back — rebuilt from the ground up for today's iPhone and iPad. FEATURES: • Mandelbrot, Julia, Newton and Multibrot fractals • Deep zoom: magnify the Mandelbrot and Julia sets more than a trillion times • Four classic palettes — Hot, Cold, Gray and Chromatic — with smooth coloring • Julia presets (Dendrite, Spiral, Rabbit, Galaxy, San Marco), Multibrot exponents 2–8, three Newton polynomials • Replay: watch your whole exploration animate back as a short movie • Picks up exactly where you left off • Free and open source Deep zoom uses K. I. Martin's perturbation technique.

SigiCalc is a fast, clean RPN calculator that draws your functions. Enter a calculation the RPN way – numbers first, then the operation – and as soon as your expression contains X, tap Graph to see it plotted. No equals key, no parentheses, no fuss. REAL RPN • Classic stack-based entry with Enter, Undo and All Clear • Keys light up only when the stack has enough values – you can't make an invalid entry • The display shows your result, the whole expression in normal notation and the raw stack LIVE FUNCTION GRAPHS • Use X as a variable and plot the result instantly • Pinch to zoom, drag to pan, tap to zoom in, double-tap to reset • Touch and hold to read the exact x / y value on the curve • Discontinuities like tan(x) or 1/x are drawn correctly – no misleading vertical lines SCIENTIFIC FUNCTIONS sin, cos, tan and their inverses, natural log, square, square root, reciprocal, sign change and π DESIGNED FOR TODAY'S DEVICES • Light and Dark Mode, portrait and landscape • iPad: calculator and live graph side by side • Smooth animations and haptic feedback PRIVATE BY DESIGN SigiCalc works entirely on your device. No account, no network, no ads, no tracking. Example: X ↲ X sin × plots x · sin(x). What changed versus your text and why: - Leads with a benefit, not a category: "draws your functions" is the hook; "simple and practical graphical" told the reader nothing they'd search for. - Explains RPN in one sentence for people who don't know it, since that's the biggest reason someone bounces. - Bulleted feature blocks — App Store descriptions are skimmed, and the capitalised headings scan well in the store's plain-text rendering. - Adds Dark Mode / iPad / privacy, all of which are new in 3.0 and are things reviewers and users look for. - Fixed "polish" → "Polish" and "equation" → "expression" (you plot expressions, not equations).