Datum vs Petra
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Datum
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.
- 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
Read full descriptionHide full description
Datum is a minimalistic iOS, watchOS, macOS and visionOS calendar app. For iOS there are Lockscreen Widgets that show you the current date and there are Lockscreen Widgets that show up to 3 events for today. The iOS and macOS apps include the following widgets: - a small widget that shows the current date and at the bottom the events for this day - a small widget that shows a calendar with up to 3 event marks for each day - a medium widget that shows the same as the first small widget and on the right side a calendar with up to 3 event marks for each day - a large widget that shows the same as the medium widget and a list of the upcoming events - a extra large widget that shows a calendar and a list of the upcoming events (only for iPadOS 15+) The watchOS app shows a calendar with up to 3 event marks for each day. You can switch to the next/previous month by tapping on the arrows at the bottom of the calendar. You can view all events for each day by tapping on a day. There are also complications for all watchfaces included that show you the current date.
Petra
Read full descriptionHide full description
Split your costs with friends and family
Screenshots
Verdict
The clearest difference is price: Petra at Free against Datum's $1.99. Datum's advantage is device support (5 vs 2). On update cadence, ads, in-app purchases and iOS requirement 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
Petra is free to download; Datum costs $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.
Both ship on a similar rhythm, roughly every 3 months. The most recent releases landed on October 9, 2026 and October 15, 2026 respectively.
| Parameter | Datum | Petra |
|---|---|---|
| Price | $1.99 | Free — better |
| Positive reviews | 100.0% of reviews | — |
| Update frequency | Every 3 months | Every 3 months |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | — |
| Devices | iPhone, iPad, Mac, Apple Watch, Vision Pro — better | iPhone, iPad |
| Requires iOS | 17.6 | 17.6 |
| Further details — not scored | ||
| Size | 11 MB | 10 MB |
| Age rating | 4+ | 4+ |
| Developer | Michael Lindinger | Mathias Palm |
In-app purchases
Datum
No in-app purchases
Petra
No in-app purchases
