# RoboTou Stacker vs Sharp

The clearest difference is update cadence: RoboTou Stacker at every 5 days against Sharp's fortnightly. RoboTou Stacker also leads on iOS requirement (17.0 vs 27.0). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. RoboTou Stacker sells 2 in-app purchases, starting at $5.00 per year and Sharp sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

RoboTou Stacker ships an update every 5 days, Sharp fortnightly. The most recent releases landed on September 29, 2026 and October 13, 2026 respectively.

## The numbers

| Metric | RoboTou Stacker | Sharp |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/robotou-stacker/id6761755082/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | **Every 5 days** | Fortnightly |
| Monetization | Free with in-app purchases | — |
| Size | 88 MB | 3 MB |
| Requires iOS | **17.0** | 27.0 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [振国 吴](https://appshunter.io/developer/1739933647) | [Pablo Miranda](https://appshunter.io/developer/821775028) |

## What reviewers say

### RoboTou Stacker

[App page](https://appshunter.io/ios/app/robotou-stacker/id6761755082)

Combine multiple photos directly on your device for enhanced results. This app offers automatic masking and alignment for various photography needs, including starry skies and light trails. Process your images locally without needing an account or cloud sync.

**Highlights:** On-device image stacking, Automatic masking and alignment, Starry sky stacking, Star trail stacking, Car-light trail stacking, Local preview generation, Export to Photos

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| RoboTou Stacker Pro Annual | $5.00 | per year |
| RoboTou Stacker Pro Lifetime | $39.99 | one-time |


### Sharp

[App page](https://appshunter.io/ios/app/sharp-multi-frame-merge/id6814299909)

**Features:** Family Sharing

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlock Sharp 12 | $9.99 | one-time |


## Frequently asked questions

### Is RoboTou Stacker free?

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

### Is Sharp free?

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

### Do RoboTou Stacker or Sharp have ads?

Neither RoboTou Stacker nor Sharp shows ads.

### Which is updated more often, RoboTou Stacker or Sharp?

RoboTou Stacker ships an update every 5 days, and Sharp fortnightly. Most recently, RoboTou Stacker was updated on September 29, 2026 and Sharp on October 13, 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.*