# Is it Sunday? — Know day of week for any date > Algorithm app to calculate the day of the week for any given date. (iPhone/iPad app by Viktor Gavrilov.) - Source: https://appshunter.io/ios/app/is-it-sunday/id1577132545 (this page in markdown: same URL + `.md`) - Developer: [Viktor Gavrilov](https://appshunter.io/developer/1324295185) - Category: Games, Business, Family, Trivia - Price: $0.99 with in-app purchases - Rating: 5.00/5 from 2 App Store ratings - Age rating: 4+ - Requires: iOS 14.1 · 4 MB - Languages: American English, Russian - Released: 2021-07-29 - Data updated: 2026-08-14 - Monetization: paid - User reviews in markdown: https://appshunter.io/ios/app/is-it-sunday/id1577132545/reviews.md ## What is Is it Sunday?? Learn how to get a day of the week for any date! What could be cooler? Learn the doomsday algorithm and everyone will think you have a superhuman memory. Even if it looks very complicated at the first time, anyone could learn it in a matter of minutes. Compare your skill vs other superhumans - compete and rise to the top of Game Center! ## Key features - Learn doomsday algorithm - Calculate day of week for any date - Develop superhuman memory - Compete with other users - Rise to the top of Game Center ## Pricing and in-app purchases Base price: $0.99. **One-time purchases** | Purchase | Price | Type | | --- | --- | --- | | Remove ads | $2.99 | one-time | ## Frequently asked questions about Is it Sunday? ### What is the doomsday algorithm in Is it Sunday? The doomsday algorithm is a method taught within Is it Sunday? that allows users to calculate the day of the week for any given date. It's designed to be learnable within minutes, even if it appears complex initially. ### How does Is it Sunday? compare to other calendar apps? Unlike standard calendar apps, Is it Sunday? focuses on teaching a specific algorithm for date calculation and includes a competitive gaming element. It's more of a mental puzzle and skill-building tool than a daily organizer. ### Can I use Is it Sunday? offline? The description does not specify offline functionality. However, the competitive features and Game Center integration suggest that an internet connection may be required for full use. ### What devices does Is it Sunday? support? Is it Sunday? is available for iPhone and iPod devices. It was last updated on September 9, 2022, with version 2022.3. ### Is Is it Sunday? suitable for children? Yes, Is it Sunday? has an age rating of 4+, making it suitable for younger users. The app's focus on learning and simple gameplay mechanics are appropriate for this age group. ### How often is Is it Sunday? updated? The app was last updated on September 9, 2022. While specific update frequency isn't detailed, this indicates it receives periodic maintenance and potential feature additions. ### What do users like about Is it Sunday? Based on the available rating of 5.0 stars from 2 ratings, users likely appreciate the unique learning aspect of the doomsday algorithm and the competitive challenge it offers. ### Does Is it Sunday? have ads? No, Is it Sunday? does not contain advertisements. The app is a paid download, priced at $0.99, and also offers in-app purchases. ## Version history (last 5 releases) ### 2022.3 — 2022-09-09 - bug fixes ### 2022.2 — 2022-09-08 - bug fixes ### 2022.1 — 2022-04-06 - set a custom date and check calculations (Practice - Custom date) - bug fixes ### 2021.4 — 2021-11-12 - bug fixes ### 2021.3 — 2021-08-04 - leaderboard bug fixed ## Apps similar to Is it Sunday? | App | Rating | Price | Category | | --- | --- | --- | --- | | [OtterDay: Calendar Logic Game](https://appshunter.io/ios/app/otterday-calendar-logic-game/id6747994124) | 5.0 (1) | Free | Games | | [Word Ladder](https://appshunter.io/ios/app/word-ladder/id1527106984) | 4.4 (119) | Free | Games | | [History Date Guesser - Quiz](https://appshunter.io/ios/app/history-date-guesser-quiz/id6476115590) | 5.0 (2) | Free | Games | | [Wikitrivia - History Quiz](https://appshunter.io/ios/app/wikitrivia-history-quiz/id1610932678) | 4.5 (38) | Free | Games | | [LDS Scripture Golf](https://appshunter.io/ios/app/lds-scripture-golf/id1186113597) | 4.6 (16) | Free | Games | | [Holy Places Quiz Game](https://appshunter.io/ios/app/holy-places-quiz-game/id1294022470) | 4.8 (130) | Free | Games | ## More apps by Viktor Gavrilov - [1440: countdown timer](https://appshunter.io/ios/app/1440-countdown-timer/id1324295186) - [Mark Off: Calendar & Tracker](https://appshunter.io/ios/app/mark-off-calendar-and-tracker/id1434848437) - [True Cost](https://appshunter.io/ios/app/true-cost/id1476296558) - [Team Splitter](https://appshunter.io/ios/app/team-splitter/id1492422081) - [Activity Map](https://appshunter.io/ios/app/activity-map/id1494633767) - [Beader](https://appshunter.io/ios/app/beader/id1522156537) All apps by Viktor Gavrilov: https://appshunter.io/developer/1324295185 --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-14.*