# ShiftProCalendar vs AtomCalendar

The clearest difference is update cadence: AtomCalendar at weekly against ShiftProCalendar's every 2 months. AtomCalendar also leads on iOS requirement (15.0 vs 17.6). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. ShiftProCalendar sells 2 in-app purchases, starting at $0.99 per month and AtomCalendar sells 5 in-app purchases, starting at $3.99 per month. Whichever you choose, the download price is not the number that matters.

ShiftProCalendar ships an update every 2 months, AtomCalendar weekly. Both last shipped on October 24, 2026.

## The numbers

| Metric | ShiftProCalendar | AtomCalendar |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 2 months | **Weekly** |
| Size | 20 MB | 92 MB |
| Requires iOS | 17.6 | **15.0** |
| Devices | iPhone, iPad, Apple Watch | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [LI JUNYI](https://appshunter.io/developer/1863692375) | [Aotter Inc.](https://appshunter.io/developer/597484493) |

## What reviewers say

### ShiftProCalendar

[App page](https://appshunter.io/ios/app/shiftprocalendar/id6761934926)

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro Monthly | $0.99 | per month |
| Pro Lifetime Access | $29.99 | one-time |


### AtomCalendar

[App page](https://appshunter.io/ios/app/atomcalendar-lucky-planner/id6805333475)

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (5)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 進階方案月繳 | $3.99 | per month |
| 進階方案年繳 | $39.99 | per year |
| 100 點原子點數 | $2.99 | one-time |
| 300 點原子點數 | $9.99 | one-time |
| 1,000 點原子點數 | $29.99 | one-time |


## Frequently asked questions

### Is ShiftProCalendar free?

ShiftProCalendar is free to download, with in-app purchases available.

### Is AtomCalendar free?

AtomCalendar is free to download, with in-app purchases available.

### Do ShiftProCalendar or AtomCalendar have ads?

Neither ShiftProCalendar nor AtomCalendar shows ads.

### Which is updated more often, ShiftProCalendar or AtomCalendar?

ShiftProCalendar ships an update every 2 months, and AtomCalendar weekly. Most recently, ShiftProCalendar was updated on October 24, 2026 and AtomCalendar on October 24, 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.*