# when - USA > Smart date and duration calculator with intuitive input methods. (iPhone/iPad app by uto toshiki.) - Source: https://appshunter.io/ios/app/when-usa/id6447483467 (this page in markdown: same URL + `.md`) - Developer: [uto toshiki](https://appshunter.io/developer/876927513) - Category: Productivity, Utilities - Price: Free - Rating: 5.00/5 from 1 App Store ratings - Age rating: 4+ - Requires: iOS 9.0 · 3 MB - Languages: English - Released: 2023-05-01 - Data updated: 2026-06-04 - Monetization: free - User reviews in markdown: https://appshunter.io/ios/app/when-usa/id6447483467/reviews.md ## What is when? Counting days and checking dates is surprisingly common in the workplace. However, it can be surprisingly stressful. This app calculates dates and durations easily and smartly with few operations. For those rare occasions, we have prepared a simple date calculator. . We are still trying our best to be ad-free. Achieve rapid results -. Use the Calendar PAD, Numeric PAD, Calendar PAD to set the date instead of rotating the date meter. ・The dedicated PAD prevents erroneous input and reduces input errors. - Show errors quickly. - Numbers are easy to read with OCR font style. About operation ・You can change by touching each item. ・To erase PAD, confirm with ENTER, input end, swipe down ・There is no calculation button. Notes about this app - before January 1, 1870. Round to January 1, 1870. ・When you press the calendar mark of the day of the week, the calendar PAD will appear. ・If the calculation result exceeds 9999 AD, the input value will be restricted. • Make the end of the month absurd (for example, 31st). The "months" displayed in the period calculation are calculated with the "months" up to the same day as the start date of the period. Months that do not have the same day as the start date are treated as "months" up to the last day. (The number of days in the month changes) Example) January 30, 2020 to March October 2020 = January 30th to February 29th → 1 month, February 29th to March 10th → 10th, March 3, 2020 to May 5, 2020 = March 3rd to May 5th → 2 months From May. 3rd to May 5th → 2 days *Excludes end date. About app settings Press the gear on the topscreen or go to [Settings] > [When] to open settings screen. About icons ・Icons can be changed on iOS 10.3 or higher ・If you switch the dark theme ON/OFF in the settings, the icon's color will change too. ## Key features - Smart date and duration calculation - Dedicated input pads for accuracy - OCR font style for readability - Quick error display - Customizable icons (iOS 10.3+) - Dark theme support ## Frequently asked questions about when ### How does When calculate durations? When calculates durations by excluding the end date. It handles month calculations by considering the number of months up to the same day as the start date, treating months without that specific day as having the last day of the month. ### What is the age rating for When? When has an age rating of 4+, making it suitable for a wide range of users. ### What devices does When support? When is available on iPhone, iPad, and iPod. ### How often is When updated? The app was last updated on May 11, 2023, with version 4.3.1. This indicates a recent update, suggesting ongoing development and support. ### What are the limitations for date calculations in When? Dates before January 1, 1870, are rounded to January 1, 1870. Calculations exceeding 9999 AD will restrict input values. ### Can I change the app icon for When? Yes, icons can be changed on iOS 10.3 or higher. Switching the dark theme ON/OFF in settings will also change the icon's color. ### Does When have ads? The developer is striving to be ad-free. Based on the provided data, the app is currently free and does not contain advertisements. ### What is the user rating for When? When has a perfect rating of 5.0 stars from 1 rating, indicating very positive user sentiment. ## Version history (last 2 releases) ### 4.3.1 — 2023-05-11 bug fix // Not disappear error mark when push 'now' button after clear. // Not appear old value when push 'enter' after clear. // Do not adjust weekNo’s year when under limit value. // Not displey month warning. // slided day's color when setting monday start at the setting. // implement the enter function to the now button . // Mistake year calculation // Can't go to function at menu selection. function change // change The calendar PAD design. // change design icon and select menu. ### 4.3 — 2023-05-01 No release notes. ## Apps similar to when | App | Rating | Price | Category | | --- | --- | --- | --- | | [Lost Time: Day Journal](https://appshunter.io/ios/app/lost-time-day-journal/id6736591132) | 5.0 (9) | Free | Productivity | | [10MB: Time Tracking, Made Easy](https://appshunter.io/ios/app/10mb-time-tracking-made-easy/id1599243769) | 5.0 (8) | Free | Productivity | | [Widgetminder](https://appshunter.io/ios/app/widgetminder/id6503644365) | 4.8 (4) | Free | Productivity | | [Almost Time: Event Countdowns](https://appshunter.io/ios/app/almost-time-event-countdowns/id1569126187) | 3.8 (4) | Free | Productivity | | [Simple Notes, Notepad & Lists](https://appshunter.io/ios/app/simple-notes-notepad-and-lists/id6749871033) | 4.9 (22) | Free | Productivity | | [Schedule!](https://appshunter.io/ios/app/schedule/id1566795624) | — | Free | Productivity | ## More apps by uto toshiki - [calcS16lite](https://appshunter.io/ios/app/calcs16lite/id876927510) - [calcS16](https://appshunter.io/ios/app/calcs16/id962408149) - [colorChopper](https://appshunter.io/ios/app/colorchopper/id965910925) - [fucusViewFree](https://appshunter.io/ios/app/fucusviewfree/id972447348) - [Coro.](https://appshunter.io/ios/app/coro/id1017066209) - [Coros.](https://appshunter.io/ios/app/coros/id1022442989) All apps by uto toshiki: https://appshunter.io/developer/876927513 --- *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 2026-06-04.*