# Ondi vs Cycle Sync

The clearest difference is ads: Ondi at none against Cycle Sync's shown. Ondi also leads on update cadence (weekly vs every 2 months). On price, in-app purchases, device support and iOS requirement there is nothing between them.

Both are free to download. Ondi sells 1 one-off in-app purchase and Cycle Sync sells 3 in-app purchases, starting at $4.99 per 7 days. Whichever you choose, the download price is not the number that matters.

Ondi ships an update weekly, Cycle Sync every 2 months. The most recent releases landed on October 28, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Ondi | Cycle Sync |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | Yes |
| Ads | **No** | Yes |
| Update frequency | **Weekly** | Every 2 months |
| Size | 10 MB | 78 MB |
| Requires iOS | **17.0** | 18.2 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 12+ | 4+ |
| Developer | [Blue Flame Games](https://appshunter.io/developer/523824138) | [Amit Kairon](https://appshunter.io/developer/1750611800) |

## What reviewers say

### Ondi

[App page](https://appshunter.io/ios/app/ondi-private-period-tracker/id6760896784)

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Cyla Premium | $7.99 | one-time |


### Cycle Sync

[App page](https://appshunter.io/ios/app/cycle-sync-smart-menstruation/id6772445948)

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| CycleSync Pro — Weekly | $4.99 | per 7 days |
| CycleSync Pro | $9.99 | per month |
| CycleSync Pro | $59.99 | per year |


## Frequently asked questions

### Is Ondi free?

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

### Is Cycle Sync free?

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

### Do Ondi or Cycle Sync have ads?

Cycle Sync shows ads; Ondi does not.

### Which is updated more often, Ondi or Cycle Sync?

Ondi ships an update weekly, and Cycle Sync every 2 months. Most recently, Ondi was updated on October 28, 2026 and Cycle Sync 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.*