When Does vs HolyDates
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
When Does
This app provides the dates for numerous holidays and observances throughout the year. Users can easily add these events to their personal calendars or send them via email to themselves or others. It's a convenient reference for tracking important dates, including major holidays and time changes.
- Holiday date lookup
- Add holidays to calendar
- Email holiday information
- Includes major holidays
- Tracks US Daylight Saving Time
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When Does tells you when a number of holidays occur in a given year. It allows you to add the holiday to your calendar or to email it to you or to someone else. If you want to know when a holiday occurs, look here! It includes Chinese New Year, Martin Luther King Day, Valentine's Day, St. Patrick's Day, Easter, Passover, and many more! It also includes the start and end of US Daylight Savings Time.
HolyDates
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Version 1.10 No Advertisements, No In-App Purchases Did you ever need to look-up when Easter Sunday or Passover will be this year? Even though many of the religious holydays occur on the same date of the Hebrew calendar every year you may not know the corresponding date on the Gregorian calendar. HolyDates provides a quick answer to these questions. HolyDates uses algorithms provided by Jean Meeus in his book, “Astronomical Algorithms” second edition. His methods have become a sort-of standard for these sorts of computations. The information and functionality provided by HolyDates is divided onto several screens. The Main Screen: The day and date for eleven holy days are shown on the main screen. • Passover • Easter • Unleavened Bread (aka .Matzo) – seven days in length • First Fruits (two methods for determining this date) • Shavuot (two methods for determining this date) • Pentecost • Rosh Hashanah (aka Yom Teruach, Feast of Trumpets, New Year Day) • Yom Kippur (aka Day of Atonement) • Sukkot (aka Feast of Booths, Feast of Weeks, Feast of Tabernacles) The Julian Day Number Screen: Julian Day Numbers are used by astronomers to keep track of dates or perform date-related computations. HolyDates provides a separate screen for converting between the two systems. You can: • convert Gregorian Dates to Julian Day Number • convert Julian Day Numbers to Gregorian Dates The Information Screen: This is the HolyDates help file that provides additional background information. The origin of the modern calendar system and how HolyDates works are discussed.
Screenshots
Verdict
The clearest difference is update cadence: When Does at every 5 months against HolyDates's every 34 months. HolyDates's advantage is device support (5 vs 3) and iOS requirement (12.4 vs 15.6). On price, ads and in-app purchases there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
When Does costs $0.99 and HolyDates $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.
When Does ships an update every 5 months, HolyDates every 34 months. The most recent releases landed on June 4, 2026 and October 5, 2026 respectively.
| Parameter | When Does | HolyDates |
|---|---|---|
| Price | $0.99 | $0.99 |
| Rating | 5.0 (2 ratings) — better | — |
| Positive reviews | 100.0% of reviews | — |
| Number of ratings | 2 — better | — |
| Update frequency | Every 5 months — better | Every 34 months |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | — |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod, Mac, Apple TV — better |
| Requires iOS | 15.6 | 12.4 — better |
| Further details — not scored | ||
| Size | 47 MB | 2 MB |
| Age rating | 4+ | 4+ |
| Developer | Paul T Cottey | Tom Stankey |
In-app purchases
When Does
No in-app purchases
HolyDates
No in-app purchases







