# Stackr vs 21 Pilates NYC

The clearest difference is in-app purchases: 21 Pilates NYC at none against Stackr's 7. Stackr's advantage is update cadence (weekly vs every 2 weeks). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Stackr sells 7 in-app purchases, starting at $7.99 per 7 days. 21 Pilates NYC asks for nothing beyond the download.

Stackr ships an update weekly, 21 Pilates NYC every 2 weeks. The most recent releases landed on October 29, 2026 and October 12, 2026 respectively.

## The numbers

| Metric | Stackr | 21 Pilates NYC |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.4 (198 ratings)](https://appshunter.io/ios/app/stackr-peptide-glp-1-tracker/id6764821587/reviews)** | — |
| Number of ratings | **198** | — |
| Positive reviews | 68.8% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Weekly** | Every 2 weeks |
| Monetization | Freemium | — |
| Size | 88 MB | 192 MB |
| Requires iOS | 17.0 | **16.0** |
| Devices | iPhone | **iPhone, iPad** |
| Age rating | 12+ | 4+ |
| Developer | [Stackr Holdings LLC](https://appshunter.io/developer/1896525659) | [21 PilatesNYC LLC](https://appshunter.io/developer/6791960015) |

## What reviewers say

### Stackr

[App page](https://appshunter.io/ios/app/stackr-peptide-glp-1-tracker/id6764821587)

This app simplifies tracking peptide and GLP-1 doses, including supplies like vials and pens. It offers smart reminders, home screen widgets, and visual charts of estimated active levels based on half-life. Designed for users managing peptide protocols, it keeps your dosing information organized and accessible.

**Highlights:** Log peptide and GLP-1 doses, Track vials, pens, and other supplies, Smart reminders for next doses, Home screen widgets, Estimated active level charts, Multi-peptide stack tracking, Reference pages for common compounds

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

**In-app purchases (7)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Stackr+ Weekly | $7.99 | per 7 days |
| Monthly | $12.99 | per month |
| Stackr+ Yearly | $29.99 | per year |
| Stackr+ Yearly | $49.99 | per year |
| Stackr+ Yearly | $49.99 | per year |
| Stackr+ Yearly | $59.99 | per year |
| Yearly | $69.99 | per year |


### 21 Pilates NYC

[App page](https://appshunter.io/ios/app/21-pilates-nyc/id6791960013)

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

**In-app purchases:** none


## Frequently asked questions

### Is Stackr free?

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

### Is 21 Pilates NYC free?

21 Pilates NYC is free to download, with no in-app purchases.

### Do Stackr or 21 Pilates NYC have ads?

Neither Stackr nor 21 Pilates NYC shows ads.

### Which is updated more often, Stackr or 21 Pilates NYC?

Stackr ships an update weekly, and 21 Pilates NYC every 2 weeks. Most recently, Stackr was updated on October 29, 2026 and 21 Pilates NYC on October 12, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*