# Occult Science vs Grimorio

The clearest difference is ads: Occult Science at none against Grimorio's shown. Grimorio's advantage is update cadence (every 4 days vs every 10 months). On price, in-app purchases, device support and iOS requirement there is nothing between them.

Both are free to download. Occult Science sells 1 one-off in-app purchase and Grimorio sells 2 in-app purchases, starting at $2.99 per month. Whichever you choose, the download price is not the number that matters.

Occult Science ships an update every 10 months, Grimorio every 4 days. The most recent releases landed on September 23, 2026 and September 19, 2026 respectively.

## The numbers

| Metric | Occult Science | Grimorio |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 10 months | **Every 4 days** |
| Size | 324 MB | 173 MB |
| Requires iOS | 13.0 | 13.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 12+ |
| Developer | [ALL INDIA INSTITUTE OF OCCULT SCIENCE](https://appshunter.io/developer/1610107660) | [Blank Tech](https://appshunter.io/developer/1889611867) |

## What reviewers say

### Occult Science

[App page](https://appshunter.io/ios/app/occult-science/id1610107658)

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Diploma in Tarot 2022-Batch 3 | $22.99 | one-time |


### Grimorio

[App page](https://appshunter.io/ios/app/grimorio/id6761935740)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Grimorio Pro Monthly | $2.99 | per month |
| Grimorio Pro Annual | $24.99 | per year |


## Frequently asked questions

### Is Occult Science free?

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

### Is Grimorio free?

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

### Do Occult Science or Grimorio have ads?

Grimorio shows ads; Occult Science does not.

### Which is updated more often, Occult Science or Grimorio?

Occult Science ships an update every 10 months, and Grimorio every 4 days. Most recently, Occult Science was updated on September 23, 2026 and Grimorio on September 19, 2026.

---

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