# popi vs Kidney Notes for Cats

The clearest difference is in-app purchases: popi at none against Kidney Notes for Cats's 2. popi also leads on iOS requirement (14.0.0 vs 16.4). Kidney Notes for Cats's advantage is update cadence (every 5 days vs every 2 months). On price, ads and device support there is nothing between them.

Both are free to download. Kidney Notes for Cats sells 2 in-app purchases, starting at $4.99 per month. popi asks for nothing beyond the download.

popi ships an update every 2 months, Kidney Notes for Cats every 5 days. The most recent releases landed on October 13, 2026 and October 14, 2026 respectively.

## The numbers

| Metric | popi | Kidney Notes for Cats |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 2 months | **Every 5 days** |
| Size | 64 MB | 36 MB |
| Requires iOS | **14.0.0** | 16.4 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [nana suemasa](https://appshunter.io/developer/1874499855) | [STEELSTYLE K.K.](https://appshunter.io/developer/1547579860) |

## What reviewers say

### popi

[App page](https://appshunter.io/ios/app/popi/id6758689311)

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

**In-app purchases:** none


### Kidney Notes for Cats

[App page](https://appshunter.io/ios/app/kidney-notes-for-cats/id6803513033)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| プレミアム（月額） | $4.99 | per month |
| プレミアム（年額） | $34.99 | per year |


## Frequently asked questions

### Is popi free?

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

### Is Kidney Notes for Cats free?

Kidney Notes for Cats is free to download, with in-app purchases available.

### Do popi or Kidney Notes for Cats have ads?

Neither popi nor Kidney Notes for Cats shows ads.

### Which is updated more often, popi or Kidney Notes for Cats?

popi ships an update every 2 months, and Kidney Notes for Cats every 5 days. Most recently, popi was updated on October 13, 2026 and Kidney Notes for Cats on October 14, 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.*