Relativity Widget vs World Date Converter

Relativity Widget allows you to visualise Einstein's theories of relativity right on your home screen. Two modes : • Special Relativity: imagine that you are in a spaceship travelling at a chosen speed. If you travel fast enough, time will pass differently on earth... • General Relativity: you are on earth while a friend of yours went on a journey, in a spaceship, at a chosen distance to a Schwarzschild black hole. If you are close enough, time will pass differently in the spaceship... Relativity Widget clocks represent the difference in time flow, since midnight, between a high speed / high gravity experiencing reference frame and a low speed / gravity one, according to Einstein's theory of relativity.

World Date Converter is the cleanest way to convert any date between the world's calendars — instantly and completely offline, with no sign-up. SUPPORTED CALENDARS • Gregorian • Persian / Shamsi (Jalali) with Afghan month names • Islamic / Hijri (Umm al-Qura & tabular) • Hebrew • Chinese (with zodiac) • Buddhist (Thai) • Indian (Saka) • Coptic • Ethiopic • Japanese (era) FEATURES • Every month name in its own script AND clear Latin transliteration • See one date in every calendar at once • Add any converted date to your phone's calendar — one tap, no account • 30 languages with full right-to-left support • Works 100% offline. Private by design — no sign-up, nothing leaves your device. Note: the Islamic date is the tabular/Umm al-Qura calculation; official religious dates (Ramadan, Eid) are set by moon sighting and may differ by a day or two.