# Mimir vs Substrata

The clearest difference is in-app purchases: Mimir at none against Substrata's 4. Mimir also leads on device support (3 vs 1) and iOS requirement (15.1 vs 26.2). Substrata's advantage is update cadence (every 4 days vs monthly). On price and ads there is nothing between them.

Both are free to download. Substrata sells 4 in-app purchases, starting at $4.99 per month. Mimir asks for nothing beyond the download.

Mimir ships an update monthly, Substrata every 4 days. The most recent releases landed on October 20, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | Mimir | Substrata |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (4 ratings)](https://appshunter.io/ios/app/substrata-headache-tracker/id6759664433/reviews)** |
| Number of ratings | — | **4** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Monthly | **Every 4 days** |
| Monetization | — | Freemium |
| Size | 50 MB | 7 MB |
| Requires iOS | **15.1** | 26.2 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [AIMS Insights](https://appshunter.io/developer/1718120299) | [Steven Knauss](https://appshunter.io/developer/1877190883) |

## What reviewers say

### Mimir

[App page](https://appshunter.io/ios/app/mimir/id6472943548)

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

**In-app purchases:** none


### Substrata

[App page](https://appshunter.io/ios/app/substrata-headache-tracker/id6759664433)

This app analyzes environmental factors like weather and noise alongside your personal health data, such as sleep and heart rate, to identify potential triggers for headaches and other symptoms. It uses on-device intelligence to provide plain-English explanations and predictive alerts, helping you understand what affects your well-being.

**Highlights:** Sleep condition scoring, Headache and symptom logging, Personal trigger profile building, Predictive alert system, On-device AI correlation, HealthKit and Apple Watch integration, PDF and CSV export

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

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Substrata Premium Monthly | $4.99 | per month |
| Substrata Premium Annual | $29.99 | per year |
| Substrata Premium | $3.99 | one-time |
| Substrata Premium Lifetime | $89.99 | one-time |


## Frequently asked questions

### Is Mimir free?

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

### Is Substrata free?

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

### Do Mimir or Substrata have ads?

Neither Mimir nor Substrata shows ads.

### Which is updated more often, Mimir or Substrata?

Mimir ships an update monthly, and Substrata every 4 days. Most recently, Mimir was updated on October 20, 2026 and Substrata on October 25, 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.*