# Cool Words I vs iSestra

The clearest difference is iOS requirement: Cool Words I at 13.0 against iSestra's 15.5. On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. Cool Words I sells 7 one-off in-app purchases and iSestra sells 1 in-app purchase, starting at $1.99 per month. Whichever you choose, the download price is not the number that matters.

Cool Words I ships an update fortnightly, iSestra monthly. The most recent releases landed on November 8, 2026 and November 9, 2026 respectively.

## The numbers

| Metric | Cool Words I | iSestra |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | **Fortnightly** | Monthly |
| Size | 66 MB | 89 MB |
| Requires iOS | **13.0** | 15.5 |
| Devices | iPhone, iPod, Apple Watch | iPhone, iPad, iPod |
| Age rating | 4+ | 17+ |
| Developer | [Kvintech solution](https://appshunter.io/developer/1055661822) | [Adam Ondru](https://appshunter.io/developer/1855471691) |

## What reviewers say

### Cool Words I

[App page](https://appshunter.io/ios/app/cool-words-i/id1542365795)

**Features:** Apple Watch app

**In-app purchases (7)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Seznamy, řady | $1.99 | one-time |
| 175 frázových sloves | $2.99 | one-time |
| 220 obchodních fr. sloves | $3.99 | one-time |
| 230 frázových sloves | $3.99 | one-time |
| 197 nepravidelných sloves | $3.99 | one-time |
| 3000 slovíček | $4.99 | one-time |
| Komplet všech slovíček | $9.99 | one-time |


### iSestra

[App page](https://appshunter.io/ios/app/isestra/id6755676798)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium přístum do aplikace | $1.99 | per month |


## Frequently asked questions

### Is Cool Words I free?

Cool Words I is free to download, with in-app purchases available.

### Is iSestra free?

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

### Do Cool Words I or iSestra have ads?

Neither Cool Words I nor iSestra shows ads.

### Which is updated more often, Cool Words I or iSestra?

Cool Words I ships an update fortnightly, and iSestra monthly. Most recently, Cool Words I was updated on November 8, 2026 and iSestra on November 9, 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.*