# One Calendar vs NADCA Defects

The clearest difference is in-app purchases: NADCA Defects at none against One Calendar's 1. One Calendar's advantage is update cadence (fortnightly vs every 2 months) and device support (4 vs 1). On price, ads and iOS requirement there is nothing between them.

Both are free to download. One Calendar sells 1 one-off in-app purchase. NADCA Defects asks for nothing beyond the download.

One Calendar ships an update fortnightly, NADCA Defects every 2 months. The most recent releases landed on October 28, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | One Calendar | NADCA Defects |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.8 (21K ratings)](https://appshunter.io/ios/app/one-calendar/id1238379385/reviews)** | — |
| Number of ratings | **21K** | — |
| Positive reviews | 80.7% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Fortnightly** | Every 2 months |
| Monetization | Free with in-app purchases | — |
| Size | 89 MB | 52 MB |
| Requires iOS | **15.0** | 16.4 |
| Devices | **iPhone, iPad, iPod, Mac** | iPhone |
| Age rating | 12+ | 4+ |
| Developer | [Code Spark](https://appshunter.io/developer/1238379384) | [Solutions Fonderie](https://appshunter.io/developer/1094095935) |

## What reviewers say

### One Calendar

[App page](https://appshunter.io/ios/app/one-calendar/id1238379385)

Consolidate all your digital calendars into a single, easy-to-read view. Manage appointments, events, and birthdays from various providers like Google, Outlook, iCloud, and more, all within one application.

**Highlights:** Integrates multiple calendar providers, Easy-to-read overview, Manage appointments and events, View birthdays, Cross-platform availability

**Features:** Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| OneCalendar premium | $5.99 | one-time |

**What reviewers like**

- 🚀 Easy to use
- 👍 Clean and simple interface
- 👍 Integrates multiple calendars
- 🚀 Syncs across devices
- 👍 Customizable colors and themes

**What reviewers complain about**

- 🐛 Syncing issues
- 🐛 Bugs and glitches
- 🔒 Lacks security features
- 🔋 Drains battery
- 👎 Restrictive features in free version

**Reported bugs**

- Sync errors
- Unresponsive buttons
- Incorrect time zone display
- Duplicate events
- Inability to delete future occurrences of recurring events

**Requested features**

- Multiple reminders for events
- Ability to edit recurring events
- Option to change event calendar after creation
- Printing support
- More customization options


### NADCA Defects

[App page](https://appshunter.io/ios/app/nadca-defects/id6755052593)

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

**In-app purchases:** none


## Frequently asked questions

### Is One Calendar free?

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

### Is NADCA Defects free?

NADCA Defects is free to download, with no in-app purchases.

### Do One Calendar or NADCA Defects have ads?

Neither One Calendar nor NADCA Defects shows ads.

### Which is updated more often, One Calendar or NADCA Defects?

One Calendar ships an update fortnightly, and NADCA Defects every 2 months. Most recently, One Calendar was updated on October 28, 2026 and NADCA Defects 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.*