# Saturday vs Subintervals

The clearest difference is ratings volume: Saturday at 155 against Subintervals's 2. On price, rating, review sentiment and update cadence there is nothing between them.

Both are free to download. Saturday sells 2 in-app purchases, starting at $5.99 per month and Subintervals sells 4 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

On the App Store both sit at effectively the same score — 5.0 for Saturday against 5.0 for Subintervals. That said, the two scores are not equally well evidenced: Saturday has 155 ratings behind it against 2, so its average is the more settled of the two. Written reviews are what separate them: 97% of Saturday's written reviews are positive against 100% of Subintervals's.

Saturday ships an update every 11 days, Subintervals weekly. The most recent releases landed on October 27, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Saturday | Subintervals |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [5.0 (155 ratings)](https://appshunter.io/ios/app/saturday-pro-fuel-and-hydration/id6444738746/reviews) | **[5.0 (2 ratings)](https://appshunter.io/ios/app/subintervals/id6479748688/reviews)** |
| Number of ratings | **155** | 2 |
| Positive reviews | 97.3% of reviews | **100.0% of reviews** |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 11 days | **Weekly** |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Size | 152 MB | 109 MB |
| Requires iOS | 17.0 | **16.4** |
| Devices | iPhone | **iPhone, iPad** |
| Age rating | +12 | 4+ |
| Developer | [Saturday Morning LLC](https://appshunter.io/developer/1617223984) | [Inaki Arroyo Nebreda](https://appshunter.io/developer/1736987639) |

## What reviewers say

### Saturday

[App page](https://appshunter.io/ios/app/saturday-pro-fuel-and-hydration/id6444738746)

This app provides personalized fueling and hydration plans for endurance athletes. It uses science-based recommendations tailored to your training and environment, eliminating guesswork and expensive coaching. Achieve your best performance with confidence.

**Highlights:** Personalized fuel and hydration plans, Science-based recommendations, Tailored to training and environment, Eliminates guesswork, Reduces reliance on coaching

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 1-month subscription | $5.99 | per month |
| 1-year subscription | $49.99 | per year |

**What reviewers like**

- 👍 Simple and intuitive user interface
- 💰 Significant cost savings compared to commercial sports nutrition products
- 🎯 Accurate personalized fueling recommendations
- ⚡ Improved athletic performance and endurance
- 🔬 Science-based approach to nutrition planning

**What reviewers complain about**

- 💵 Subscription cost ($79.99/year) may seem high for basic calculations
- 🌐 Web-based app rather than native application
- 📋 Recipe formatting designed for bulk mixing rather than per-bottle portions
- 🏊 Swim hydration recommendations may be inaccurate for some users
- 🎚️ Limited customization options for specific ingredient amounts

**Reported bugs**

- Login experience issues
- Swim hydration recommendations causing excessive bathroom breaks for some users

**Requested features**

- Per-bottle recipe breakdown instead of bulk mixing calculations
- Recovery advice and prescriptions
- Native mobile application instead of web app
- More granular ingredient customization options
- Improved swim-specific hydration recommendations


### Subintervals

[App page](https://appshunter.io/ios/app/subintervals/id6479748688)

Visualize your training data with detailed displays and interactive graphs. Customize your analysis and sync seamlessly with intervals.icu for up-to-the-minute insights into activities, events, and performance metrics.

**Highlights:** Detailed activity and event visualization, Interactive performance graphs, Seamless intervals.icu sync, Customizable data analysis, Actionable training insights

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

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Coffee | $3.99 | one-time |
| Lunch | $11.99 | one-time |
| Big Thanks | $17.99 | one-time |
| Sponsor | $44.99 | one-time |


## Frequently asked questions

### Is Saturday free?

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

### Is Subintervals free?

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

### Which has better reviews, Saturday or Subintervals?

Subintervals is rated higher. Saturday averages 5.0 out of 5 from 155 ratings, while Subintervals averages 5.0 from 2 ratings.

### Do Saturday or Subintervals have ads?

Neither Saturday nor Subintervals shows ads.

### Which is updated more often, Saturday or Subintervals?

Saturday ships an update every 11 days, and Subintervals weekly. Most recently, Saturday was updated on October 27, 2026 and Subintervals on October 24, 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.*