# Secure Notes vs ThreeDay Calendar

The clearest difference is ads: Secure Notes at none against ThreeDay Calendar's shown. Secure Notes also leads on device support (4 vs 2) and iOS requirement (15.0 vs 18.0). ThreeDay Calendar's advantage is update cadence (fortnightly vs every 8 months). On price and in-app purchases there is nothing between them.

Both are free to download. Secure Notes sells 2 in-app purchases, starting at $0.99 per month and ThreeDay Calendar sells 2 in-app purchases, starting at $0.99 per month. Whichever you choose, the download price is not the number that matters.

Secure Notes ships an update every 8 months, ThreeDay Calendar fortnightly. The most recent releases landed on October 26, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | Secure Notes | ThreeDay Calendar |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[1.0 (1 ratings)](https://appshunter.io/ios/app/secure-notes-memo-and-lists/id602769533/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 20.6% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 8 months | **Fortnightly** |
| Monetization | Free with in-app purchases | — |
| Size | 14 MB | 6 MB |
| Requires iOS | **15.0** | 18.0 |
| Devices | **iPhone, iPad, iPod, Mac** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Emanuele Floris](https://appshunter.io/developer/597490842) | [Hoein Song](https://appshunter.io/developer/6785738562) |

## What reviewers say

### Secure Notes

[App page](https://appshunter.io/ios/app/secure-notes-memo-and-lists/id602769533)

Securely store and organize your notes, ideas, and important information with advanced encryption. Protect your data with biometric authentication and access it from anywhere via cloud sync. Customize your experience with a dark mode and other preferences for peace of mind.

**Highlights:** Advanced encryption for maximum security, Intuitive note creation and editing, Password, Face ID, and Touch ID access, Cloud synchronization across devices, Dark mode and interface customization

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlimited Access | $0.99 | per month |
| Unlimited Access | $2.99 | per year |


### ThreeDay Calendar

[App page](https://appshunter.io/ios/app/threeday-calendar/id6785738560)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| ThreeDay Premium Monthly | $0.99 | per month |
| ThreeDay Premium Yearly | $9.99 | per year |


## Frequently asked questions

### Is Secure Notes free?

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

### Is ThreeDay Calendar free?

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

### Do Secure Notes or ThreeDay Calendar have ads?

ThreeDay Calendar shows ads; Secure Notes does not.

### Which is updated more often, Secure Notes or ThreeDay Calendar?

Secure Notes ships an update every 8 months, and ThreeDay Calendar fortnightly. Most recently, Secure Notes was updated on October 26, 2026 and ThreeDay Calendar on October 25, 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.*