# OnePreview vs NanoPrompt

The clearest difference is in-app purchases: OnePreview at none against NanoPrompt's 1. OnePreview also leads on update cadence (every 8 days vs monthly). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. NanoPrompt sells 1 one-off in-app purchase. OnePreview asks for nothing beyond the download.

OnePreview ships an update every 8 days, NanoPrompt monthly. The most recent releases landed on October 15, 2026 and October 5, 2026 respectively.

## The numbers

| Metric | OnePreview | NanoPrompt |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/onepreview/id6760284919/reviews)** | — |
| Number of ratings | **1** | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 8 days** | Monthly |
| Monetization | Free | — |
| Size | 9 MB | 10 MB |
| Requires iOS | **17.0** | 18.6 |
| Devices | iPhone, iPad, Mac | iPhone, iPad, Mac |
| Age rating | 4+ | 4+ |
| Developer | [培克 罗](https://appshunter.io/developer/1516557687) | [恒俭 董](https://appshunter.io/developer/947356968) |

## What reviewers say

### OnePreview

[App page](https://appshunter.io/ios/app/onepreview/id6760284919)

This app allows you to preview and interact with various developer file formats, including Markdown, code, databases, and archives, directly on your iPhone and iPad. It offers local processing for speed and privacy, with features like PDF export and structured data inspection.

**Highlights:** Markdown and MDX rendering, JSON, YAML, XML, CSV, TSV, TOML, ENV parsing, SQLite database inspection, Source code and log viewing, ZIP and TAR.GZ archive content preview, Mermaid diagrams and KaTeX math rendering, A4 PDF export for Markdown files

**Features:** Vision Pro support

**In-app purchases:** none


### NanoPrompt

[App page](https://appshunter.io/ios/app/nanoprompt/id6778705122)

**Features:** Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| NanoPrompt Pro | $2.99 | one-time |


## Frequently asked questions

### Is OnePreview free?

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

### Is NanoPrompt free?

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

### Do OnePreview or NanoPrompt have ads?

Neither OnePreview nor NanoPrompt shows ads.

### Which is updated more often, OnePreview or NanoPrompt?

OnePreview ships an update every 8 days, and NanoPrompt monthly. Most recently, OnePreview was updated on October 15, 2026 and NanoPrompt on October 5, 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.*