Parallel vs Twin Calc

Parallel. Calculate more. DO MORE AT ONCE Why calculate one thing at a time? Run 2, 3, or 4 calculations side by side, and arrange them however you like with drag and drop. No more memorizing one result just to punch it into the next — it's all already on screen. That's the whole idea behind the name. ONLY WHAT YOU NEED No bloat, no clutter. Scientific mode covers exactly what you'd expect from a real scientific calculator — nothing more, nothing less. The converter covers 57 world currencies plus Bitcoin, Ethereum, and a handful of other crypto. Simple, on purpose. YOUR HISTORY, YOUR CALL Parallel only saves what you choose to keep — each calculation with your own note attached, kept separate for standard and scientific mode. Share any result straight from history, wherever you need it. Prefer to keep it private? Lock it all behind Face ID or your passcode. MADE TO FEEL RIGHT Swipe between calculator, scientific mode, and converter. Feel every tap with haptic feedback. Add a widget to your Home Screen, or pull it up instantly from Quick Menu. MAKE IT YOURS Free with the Classic theme. Unlock 10 named themes, a set of distinctive fonts, and the 4-screen layout with Parallel Pro — a one-time purchase, no subscription, ever. Your calculator has never looked this good. No ads. No data collected. Available in 34 languages.

Twin Calc puts two independent calculators on one screen — a simple calculator app for anyone who has ever wished they had two. Compare two estimates. Split a bill two different ways. Convert on one side while you total on the other. Check last year's numbers against this year's. Open Twin Calc and calculators A and B are already there — no onboarding, no sign-up. Features - Calculator A and B stacked vertically (or side by side in landscape), each fully independent - Works just like the built-in iPhone calculator: + − × ÷, %, ±, backspace, and thousands separators - An expression line shows what you are calculating, so you never lose track - Drag the divider to resize the two calculators; double-tap to reset to half and half - Long-press a result to copy it; swipe left to delete one character - Haptic feedback (can be turned off) - History (tape) keeps your results automatically — tap to copy, or send a result back to A or B - Light and dark themes that follow your system setting - Both calculators and the split ratio are restored exactly as you left them Free - Two calculators, history, and reuse of your 3 most recent results - No ads PRO (one-time purchase) - Never retype a result again: send A's answer straight to B, or swap A and B in one tap - Bring back any past result from history - 3 extra themes: Midnight, Paper, and Mono PRO is a single one-time purchase. No subscription, no extra fees. Everything you calculate stays on your device and is never sent to a server. For iPhone (portrait and landscape).