# Paper vs Acid Interval

The clearest difference is ratings volume: Paper at 1.8K against Acid Interval's 1. Paper also leads on device support (3 vs 1) and iOS requirement (15 vs 17.0). Acid Interval's advantage is rating (5.0 vs 4.6). On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. Paper sells 6 in-app purchases, starting at $14.99 per month and Acid Interval sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

Acid Interval holds the better App Store score, 5.0 against 4.6. That said, the two scores are not equally well evidenced: Paper has 1.8K ratings behind it against 1, so its average is the more settled of the two.

Paper ships an update monthly, Acid Interval every 2 weeks. The most recent releases landed on November 7, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | Paper | Acid Interval |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.6 (1.8K ratings)](https://appshunter.io/ios/app/paper-writing-app-notes/id1476984841/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/acid-interval-focus-timer/id6815378728/reviews)** |
| Number of ratings | **1.8K** | 1 |
| Positive reviews | 71.6% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Monthly | **Every 2 weeks** |
| Monetization | Free with in-app purchases | Freemium |
| Size | 85 MB | 1 MB |
| Requires iOS | **15** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Mihhail Lapushkin](https://appshunter.io/developer/1143513743) | [Preston Carr](https://appshunter.io/developer/6815378730) |

## What reviewers say

### Paper

[App page](https://appshunter.io/ios/app/paper-writing-app-notes/id1476984841)

This app offers a clean and configurable writing environment for various creative projects. It supports Markdown and plain text, syncs with iCloud, and integrates with other tools. Users can publish drafts to popular blogging platforms and export documents in multiple formats.

**Highlights:** Gorgeous writing space, Silky-smooth typing, Deep personalization (Pro), Markdown or Plain Text support, iCloud sync, Publish to Medium, WordPress, Ghost, Export to PDF, HTML, DOCX, ePub

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

**In-app purchases (6)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro Features — Discounted | $14.99 | per month |
| Pro Features | $29.99 | per month |
| Pro Features — Discounted | $49.99 | per year |
| Pro Features | $99.99 | per year |
| Pro Features — Discounted | $99.99 | one-time |
| Pro Features | $199.99 | one-time |

**What reviewers like**

- 💗 Fantastic app
- 🎀 Great tool for writers
- 👍 Clean writing app
- 🤩 Awesome app
- 👍 Cute animations

**What reviewers complain about**

- 🐛 Glitchy and unreliable
- 💰 Paywalled features
- 🐛 Lost files and documents
- 🐛 Cursor issues
- 🐛 Buggy and unstable

**Reported bugs**

- Files randomly disappearing
- Cursor issues causing freezes
- Syncing and iCloud integration problems

**Requested features**

- Add image support
- Improve file management and recovery
- Expand font and customization options
- Implement team/collaborative writing features
- Add text formatting options like italics and bold


### Acid Interval

[App page](https://appshunter.io/ios/app/acid-interval-focus-timer/id6815378728)

This focus timer offers a visually unique approach to deep work, moving away from traditional interfaces. It provides customizable timers and engaging visual feedback to help users stay on task, even with the screen off. The app prioritizes a distraction-free experience with no account or data syncing required.

**Highlights:** Unique visual interface, Customizable timer intervals, Engaging animation mechanisms, Screen-off notifications, No account or data sync, Phone lock compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Acid Interval Pro | $2.99 | one-time |


## Frequently asked questions

### Is Paper free?

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

### Is Acid Interval free?

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

### Which has better reviews, Paper or Acid Interval?

Acid Interval is rated higher. Paper averages 4.6 out of 5 from 1.8K ratings, while Acid Interval averages 5.0 from 1 ratings.

### Do Paper or Acid Interval have ads?

Neither Paper nor Acid Interval shows ads.

### Which is updated more often, Paper or Acid Interval?

Paper ships an update monthly, and Acid Interval every 2 weeks. Most recently, Paper was updated on November 7, 2026 and Acid Interval on October 31, 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.*