# Datum vs DayNumCalc

The clearest difference is update cadence: Datum at every 3 months against DayNumCalc's every 6 months. Datum also leads on device support (5 vs 3). DayNumCalc's advantage is price ($0.99 vs $1.99) and iOS requirement (15.5 vs 17.6). On review sentiment, ads, in-app purchases and monetization model there is nothing between them.

Datum costs $1.99 and DayNumCalc $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Datum ships an update every 3 months, DayNumCalc every 6 months. The most recent releases landed on September 7, 2026 and September 10, 2026 respectively.

## The numbers

| Metric | Datum | DayNumCalc |
| --- | --- | --- |
| Price | $1.99 | **$0.99** |
| Rating | — | **[4.8 (6 ratings)](https://appshunter.io/ios/app/daynumcalc/id1633054306/reviews)** |
| Number of ratings | — | **6** |
| Positive reviews | 100.0% of reviews | 100.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 3 months** | Every 6 months |
| Monetization | Paid | Paid |
| Size | 11 MB | 1 MB |
| Requires iOS | 17.6 | **15.5** |
| Devices | **iPhone, iPad, Mac, Apple Watch, Vision Pro** | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Michael Lindinger](https://appshunter.io/developer/1431086653) | [Mayra M Martinez](https://appshunter.io/developer/1633054308) |

## What reviewers say

### Datum

[App page](https://appshunter.io/ios/app/datum-calendar/id1552646317)

A minimalist calendar application designed for Apple devices, offering a clean interface and customizable widgets for iOS, macOS, and watchOS. View upcoming events, daily schedules, and monthly overviews directly from your home screen or watch face.

**Highlights:** Minimalist calendar interface, Lockscreen widgets for iOS, Event display widgets, Calendar widgets with event marks, watchOS calendar and complications, Support for iPhone, iPad, Mac, and Apple Watch

**Features:** Apple Watch app

**In-app purchases:** none


### DayNumCalc

[App page](https://appshunter.io/ios/app/daynumcalc/id1633054306)

This utility app provides quick access to date calculations, including finding the day number for any date, determining a date from a day number, calculating the difference between two dates, and checking the day of the week. It also offers widgets for convenient access on your home and lock screens.

**Highlights:** Calculate day number from date, Determine date from day number, Calculate days between two dates, Add/subtract days from a date, Check day of the week, Home screen widgets, Today View widgets, Lock screen widgets

**In-app purchases:** none


## Frequently asked questions

### Is Datum free?

Datum costs $1.99, with no in-app purchases.

### Is DayNumCalc free?

DayNumCalc costs $0.99, with no in-app purchases.

### Do Datum or DayNumCalc have ads?

Neither Datum nor DayNumCalc shows ads.

### Which is updated more often, Datum or DayNumCalc?

Datum ships an update every 3 months, and DayNumCalc every 6 months. Most recently, Datum was updated on September 7, 2026 and DayNumCalc on September 10, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*