# Peptide Calculator vs MyStack

The clearest difference is iOS requirement: MyStack at 15.1 against Peptide Calculator's 18.0. On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. Peptide Calculator sells 11 in-app purchases, starting at $0.99 per 7 days and MyStack sells 2 in-app purchases, starting at $9.99 per month. Whichever you choose, the download price is not the number that matters.

Both ship on a similar rhythm, roughly every 2 weeks. The most recent releases landed on September 23, 2026 and September 11, 2026 respectively.

## The numbers

| Metric | Peptide Calculator | MyStack |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.8 (396 ratings)](https://appshunter.io/ios/app/peptide-calculator-pepflow/id6740525224/reviews)** | — |
| Number of ratings | **396** | — |
| Positive reviews | 76.9% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 2 weeks | Every 2 weeks |
| Monetization | Free with in-app purchases | — |
| Size | 135 MB | 46 MB |
| Requires iOS | 18.0 | **15.1** |
| Devices | iPhone, iPad | iPhone, iPod |
| Age rating | 4+ | 17+ |
| Developer | [keinois OU](https://appshunter.io/developer/1597616328) | [2 Man Limited](https://appshunter.io/developer/1690228719) |

## What reviewers say

### Peptide Calculator

[App page](https://appshunter.io/ios/app/peptide-calculator-pepflow/id6740525224)

Calculate peptide dosages and reconstitution accurately and quickly. Track your injections with timely reminders and live activities. Save custom formulas and sync across devices for seamless management.

**Highlights:** Peptide dosage calculation, Reconstitution guidance, Injection time tracking, Custom formula saving, Widget for daily doses, Reminders and Live Activities, iCloud sync across devices

**Features:** Family Sharing

**In-app purchases (11)**

| Purchase | Price | Billing |
| --- | --- | --- |
| PepFlow PRO (Weekly) | $0.99 | per 7 days |
| PepFlow PRO (Monthly) | $2.99 | per month |
| PepFlow PRO (Weekly) | $2.99 | per 7 days |
| Peptide PRO (Weekly) | $2.99 | per 7 days |
| PepFlow PRO (Weekly) | $3.99 | per 7 days |
| PepFlow PRO (Annual) | $8.99 | per year |
| PepFlow PRO (Monthly) | $9.99 | per month |
| Peptide PRO (Annual) | $14.99 | per year |
| Peptide PRO (Annual) | $19.99 | per year |
| PepFlow PRO (Annual) | $29.99 | per year |
| Peptide PRO (Annual) | $44.99 | per year |


### MyStack

[App page](https://appshunter.io/ios/app/mystack-peptide-tracker/id6768515225)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro Monthly | $9.99 | per month |
| Pro Mannual | $49.99 | per year |


## Frequently asked questions

### Is Peptide Calculator free?

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

### Is MyStack free?

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

### Do Peptide Calculator or MyStack have ads?

Neither Peptide Calculator nor MyStack shows ads.

### Which is updated more often, Peptide Calculator or MyStack?

Peptide Calculator ships an update every 2 weeks, and MyStack every 2 weeks. Most recently, Peptide Calculator was updated on September 23, 2026 and MyStack on September 11, 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.*