# ZeroOneFlow vs Astronomy Picture

The clearest difference is in-app purchases: Astronomy Picture at none against ZeroOneFlow's 1. On price, update cadence, ads and device support there is nothing between them.

Both are free to download. ZeroOneFlow sells 1 one-off in-app purchase. Astronomy Picture asks for nothing beyond the download.

ZeroOneFlow ships an update every 3 weeks, Astronomy Picture fortnightly. The most recent releases landed on October 7, 2026 and October 17, 2026 respectively.

## The numbers

| Metric | ZeroOneFlow | Astronomy Picture |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 3 weeks | **Fortnightly** |
| Size | 1 MB | 25 MB |
| Requires iOS | 16.2 | **15.6** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Fu Ni](https://appshunter.io/developer/1560534229) | [Edwin Mejia](https://appshunter.io/developer/1620400021) |

## What reviewers say

### ZeroOneFlow

[App page](https://appshunter.io/ios/app/zerooneflow/id1563516711)

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Tornado | $0.99 | one-time |


### Astronomy Picture

[App page](https://appshunter.io/ios/app/astronomy-picture-apod/id6475737010)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is ZeroOneFlow free?

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

### Is Astronomy Picture free?

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

### Do ZeroOneFlow or Astronomy Picture have ads?

Neither ZeroOneFlow nor Astronomy Picture shows ads.

### Which is updated more often, ZeroOneFlow or Astronomy Picture?

ZeroOneFlow ships an update every 3 weeks, and Astronomy Picture fortnightly. Most recently, ZeroOneFlow was updated on October 7, 2026 and Astronomy Picture on October 17, 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.*