# Eris vs Shadow OS

The clearest difference is update cadence: Shadow OS at weekly against Eris's fortnightly. Shadow OS also leads on iOS requirement (15.1 vs 18.0). Eris's advantage is ratings volume (13 vs 4). On price, rating, ads and in-app purchases there is nothing between them.

Both are free to download. Eris sells 6 in-app purchases, starting at $3.99 per month and Shadow OS sells 3 in-app purchases, starting at $9.99 per month. Whichever you choose, the download price is not the number that matters.

On the App Store both sit at effectively the same score — 4.8 for Eris against 4.8 for Shadow OS. Both are backed by a comparable volume of ratings — 13 and 4 respectively.

Eris ships an update fortnightly, Shadow OS weekly. The most recent releases landed on October 25, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Eris | Shadow OS |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.8 (13 ratings)](https://appshunter.io/ios/app/eris-compatibility-astrology/id6463466172/reviews)** | [4.8 (4 ratings)](https://appshunter.io/ios/app/shadow-os/id6757407948/reviews) |
| Number of ratings | **13** | 4 |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Fortnightly | **Weekly** |
| Monetization | Free with in-app purchases | Freemium |
| Size | 51 MB | 52 MB |
| Requires iOS | 18.0 | **15.1** |
| Devices | iPhone, iPad | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Palas Technologies Ltd](https://appshunter.io/developer/1537253623) | [Phonix & Aura LLC](https://appshunter.io/developer/1866703420) |

## What reviewers say

### Eris

[App page](https://appshunter.io/ios/app/eris-compatibility-astrology/id6463466172)

Gain personalized astrological insights with your complete birth chart and daily transit tracking. Explore romantic compatibility and understand planetary movements tailored to your birth details. Offers clear, meaningful interpretations for daily guidance.

**Highlights:** Complete birth chart analysis, Romantic compatibility exploration, Daily transit tracking, Moon phase and house insights, Personalized planetary movement interpretations

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

**In-app purchases (6)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Eris | $3.99 | per month |
| Eris | $4.99 | per month |
| Eris | $4.99 | per month |
| Eris | $9.99 | per month |
| Eris | $9.99 | per month |
| Eris | $49.99 | per year |


### Shadow OS

[App page](https://appshunter.io/ios/app/shadow-os/id6757407948)

This app helps you understand your personal patterns by tracking your choices, habits, and daily signals. It provides weekly and monthly insights into what connects, repeats, and changes in your behavior, offering a data-driven approach to self-awareness without dictating actions.

**Highlights:** Track daily signals and check-ins, Analyze habits and timing, Receive weekly and monthly reads, Explore Jung-inspired archetypes, Compare baseline to actual choices, View evidence behind insights

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Shadow OS Premium | $9.99 | per month |
| Shadow OS Annual | $79.99 | per year |
| Shadow OS Lifetime | $129.00 | one-time |


## Frequently asked questions

### Is Eris free?

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

### Is Shadow OS free?

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

### Which has better reviews, Eris or Shadow OS?

Eris is rated higher. Eris averages 4.8 out of 5 from 13 ratings, while Shadow OS averages 4.8 from 4 ratings.

### Do Eris or Shadow OS have ads?

Neither Eris nor Shadow OS shows ads.

### Which is updated more often, Eris or Shadow OS?

Eris ships an update fortnightly, and Shadow OS weekly. Most recently, Eris was updated on October 25, 2026 and Shadow OS 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.*