Rosetta: Unit Converter
Offline currency & measurement
Only for iPhone
Free · Designed for iPhone. Not verified for macOS.
iPhone
Star up to ten favorites for one-tap reuse. Currency rates from the European Central Bank, cached for offline. No accounts. No ads. No tracking. Ever.
Translate measurements instantly. A calm, ad-free unit converter for everyday checks — currency, weight, length, temperature, and ten more categories.
Tap either side to make it the active value; both cards are first-class, so you can convert in either direction with one tap. Star up to ten favorites for one-tap reuse from the home screen. Currency rates come from the European Central Bank — cached after your first fetch, so they keep working offline.
THIRTEEN CATEGORIES
• Currency — 165 ISO currencies, ECB-sourced rates
• Length — meters, feet, miles, kilometers, yards, inches
• Mass — grams, kilograms, pounds, ounces, stones
• Temperature — Celsius, Fahrenheit, Kelvin
• Volume — liters, gallons, cups, fluid ounces, milliliters
• Speed — m/s, km/h, mph, knots
• Area — m², ft², acres, hectares
• Time, Energy, Power, Pressure, Data, Angle
WHY ROSETTA IS DIFFERENT
• No ads. No tracking. No accounts. No analytics SDK ships in the app.
• No settings to configure. The defaults are the right defaults.
• Works offline. Currency rates cache after one online fetch; everything else needs no network at all.
• Two-way input — convert in either direction with a single tap.
• Tap any result to copy. A quiet "Copied" toast confirms.
• Light and dark mode automatic, with locale-aware number formatting and gentle haptics.
Free. Forever free. Made by Optiwise.
Support: contact@optiwise.us
Site: rosetta.optiwise.us
Ratings & Reviews
- This app has not received enough ratings or reviews to display an overview.
The developer, Optiwise, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Provider
- Optiwise
- Size
- 36.9 MB
- Category
- Utilities
- Compatibility
Requires iOS 15.1 or later.
- iPhone
Requires iOS 15.1 or later. - iPod touch
Requires iOS 15.1 or later. - Mac
Requires macOS 12.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Copyright
- © Optiwise 2026