# Notesync.md vs Dioptra

The clearest difference is in-app purchases: Notesync.md at none against Dioptra's 3. Notesync.md also leads on update cadence (daily vs fortnightly). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Dioptra sells 3 one-off in-app purchases. Notesync.md asks for nothing beyond the download.

Notesync.md ships an update daily, Dioptra fortnightly. The most recent releases landed on November 5, 2026 and November 10, 2026 respectively.

## The numbers

| Metric | Notesync.md | Dioptra |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Daily** | Fortnightly |
| Size | 2 MB | 5 MB |
| Requires iOS | 17.0 | 17.0 |
| Devices | **iPhone, iPad, Mac** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Kristopher Linquist](https://appshunter.io/developer/921302972) | [Zachary Griffin](https://appshunter.io/developer/1813803229) |

## What reviewers say

### Notesync.md

[App page](https://appshunter.io/ios/app/notesyncmd/id6763802260)

**Features:** Vision Pro support

**In-app purchases:** none


### Dioptra

[App page](https://appshunter.io/ios/app/dioptra-glb-3d-model-viewer/id6812574588)

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Small Tip | $0.99 | one-time |
| Tip | $1.99 | one-time |
| Generous Tip | $4.99 | one-time |


## Frequently asked questions

### Is Notesync.md free?

Notesync.md is free to download, with no in-app purchases.

### Is Dioptra free?

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

### Do Notesync.md or Dioptra have ads?

Neither Notesync.md nor Dioptra shows ads.

### Which is updated more often, Notesync.md or Dioptra?

Notesync.md ships an update daily, and Dioptra fortnightly. Most recently, Notesync.md was updated on November 5, 2026 and Dioptra on November 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.*