# HYDROX vs Parallel

The clearest difference is in-app purchases: Parallel at none against HYDROX's 4. Parallel also leads on update cadence (every 2 days vs weekly) and iOS requirement (15.1 vs 17.0). HYDROX's advantage is ratings volume (4 vs 1). On price, rating, ads and device support there is nothing between them.

Both are free to download. HYDROX sells 4 in-app purchases, starting at $0.99 per 7 days. Parallel asks for nothing beyond the download.

On the App Store both sit at effectively the same score — 5.0 for HYDROX against 5.0 for Parallel. Both are backed by a comparable volume of ratings — 4 and 1 respectively.

HYDROX ships an update weekly, Parallel every 2 days. The most recent releases landed on October 2, 2026 and September 30, 2026 respectively.

## The numbers

| Metric | HYDROX | Parallel |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [5.0 (4 ratings)](https://appshunter.io/ios/app/hydrox-training-hydration/id6758163738/reviews) | [5.0 (1 ratings)](https://appshunter.io/ios/app/parallel-squat-analysis/id6784048575/reviews) |
| Number of ratings | **4** | 1 |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Weekly | **Every 2 days** |
| Monetization | Freemium | **Free** |
| Size | 8 MB | 91 MB |
| Requires iOS | 17.0 | **15.1** |
| Devices | **iPhone, iPad, Apple Watch** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [BALL VENTURES LLC](https://appshunter.io/developer/1871278776) | [KRISTIN,WARLTIER AUSTIN](https://appshunter.io/developer/6784048577) |

## What reviewers say

### HYDROX

[App page](https://appshunter.io/ios/app/hydrox-training-hydration/id6758163738)

This app calculates your personalized daily hydration target based on body weight and training intensity, using scientific protocols. It offers one-tap logging, smart reminders, and advanced features for athletes and fitness enthusiasts. Syncs with HealthKit and offers an Apple Watch app.

**Highlights:** Personalized hydration targets, Training intensity adjustment, One-tap logging, Smart reminders, HealthKit sync, Apple Watch app, Widgets for home and lock screen

**Features:** macOS Compatibility

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| HYDROX Pro | $0.99 | per 7 days |
| HYDROX Pro | $24.99 | per year |
| HYROX Americas DC Race Pack | $14.99 | one-time |
| HYROX Miami Race Pack | $14.99 | one-time |


### Parallel

[App page](https://appshunter.io/ios/app/parallel-squat-analysis/id6784048575)

Record and analyze your squat form to improve depth and consistency. Get instant feedback on your angle and rep count. Optimize your training with detailed insights.

**Highlights:** Squat depth analysis, Rep counting, Consistency scoring, Form angle measurement, Quick analysis

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

**In-app purchases:** none


## Frequently asked questions

### Is HYDROX free?

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

### Is Parallel free?

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

### Which has better reviews, HYDROX or Parallel?

HYDROX and Parallel are both rated 5.0 out of 5 on the App Store, from 4 and 1 ratings respectively.

### Do HYDROX or Parallel have ads?

Neither HYDROX nor Parallel shows ads.

### Which is updated more often, HYDROX or Parallel?

HYDROX ships an update weekly, and Parallel every 2 days. Most recently, HYDROX was updated on October 2, 2026 and Parallel on September 30, 2026.

---

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