# ImpressionIST® vs i

The clearest difference is update cadence: i at every 5 weeks against ImpressionIST®'s every 3 months. On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

ImpressionIST® ships an update every 3 months, i every 5 weeks. The most recent releases landed on September 5, 2026 and September 18, 2026 respectively.

## The numbers

| Metric | ImpressionIST® | i |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 3 months | **Every 5 weeks** |
| Size | 22 MB | 166 MB |
| Requires iOS | **11.0** | 12.0 |
| Devices | iPad | iPad |
| Age rating | 4+ | 12+ |
| Developer | [Rodenstock GmbH](https://appshunter.io/developer/393510098) | [宁波明星科技发展有限公司](https://appshunter.io/developer/1271975555) |

## What reviewers say

### ImpressionIST®

[App page](https://appshunter.io/ios/app/impressionist/id1239793137)

**Features:** macOS Compatibility

**In-app purchases:** none


### i

[App page](https://appshunter.io/ios/app/i-optik-optometry/id1271975556)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is ImpressionIST® free?

ImpressionIST® is free to download, with no in-app purchases.

### Is i free?

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

### Do ImpressionIST® or i have ads?

Neither ImpressionIST® nor i shows ads.

### Which is updated more often, ImpressionIST® or i?

ImpressionIST® ships an update every 3 months, and i every 5 weeks. Most recently, ImpressionIST® was updated on September 5, 2026 and i on September 18, 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.*