# Stack vs Protodose

The clearest difference is update cadence: Stack at every 8 days against Protodose's every 3 months. Protodose's advantage is iOS requirement (16.6 vs 18.0). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Stack sells 2 in-app purchases, starting at $9.99 per 7 days and Protodose sells 2 in-app purchases, starting at $4.99 per month. Whichever you choose, the download price is not the number that matters.

Stack ships an update every 8 days, Protodose every 3 months. Both last shipped on October 1, 2026.

## The numbers

| Metric | Stack | Protodose |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | **Every 8 days** | Every 3 months |
| Size | 136 MB | 30 MB |
| Requires iOS | 18.0 | **16.6** |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 17+ | 4+ |
| Developer | [Amari Thomas](https://appshunter.io/developer/1868315587) | [Pinak Faldu](https://appshunter.io/developer/1850148588) |

## What reviewers say

### Stack

[App page](https://appshunter.io/ios/app/stack-peptide-tracker/id6773488687)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Stack Weekly | $9.99 | per 7 days |
| Stack Yearly | $49.99 | per year |


### Protodose

[App page](https://appshunter.io/ios/app/protodose-peptide-tracker/id6775407351)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Full App Access | $4.99 | per month |
| Full App Access | $39.99 | per year |


## Frequently asked questions

### Is Stack free?

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

### Is Protodose free?

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

### Do Stack or Protodose have ads?

Neither Stack nor Protodose shows ads.

### Which is updated more often, Stack or Protodose?

Stack ships an update every 8 days, and Protodose every 3 months. Most recently, Stack was updated on October 1, 2026 and Protodose on October 1, 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.*