# MERS eTextbook vs Catholic DSI

The clearest difference is update cadence: MERS eTextbook at every 3 months against Catholic DSI's every 8 months. Catholic DSI's advantage is device support (3 vs 1) and iOS requirement (11.0 vs 18.6). On price, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

MERS eTextbook ships an update every 3 months, Catholic DSI every 8 months. The most recent releases landed on October 23, 2026 and October 26, 2026 respectively.

## The numbers

| Metric | MERS eTextbook | Catholic DSI |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 16.7% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 3 months** | Every 8 months |
| Monetization | Free | — |
| Size | 66 MB | 11 MB |
| Requires iOS | 18.6 | **11.0** |
| Devices | iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Modern Educational Research Society, LTD](https://appshunter.io/developer/432268704) | [eClass Limited](https://appshunter.io/developer/1683448274) |

## What reviewers say

### MERS eTextbook

[App page](https://appshunter.io/ios/app/mers-etextbook/id559730704)

This application allows students to download and access eTextbooks from their school. It provides interactive learning tools, multimedia content, and tracks user progress. Content is personalized based on user login and school affiliation.

**Highlights:** Downloadable eTextbooks, Personalized content by school, Interactive learning tools, Multimedia integration, Learning history tracking, Notifications for new content

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

**In-app purchases:** none


### Catholic DSI

[App page](https://appshunter.io/ios/app/catholic-dsi/id1432383432)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is MERS eTextbook free?

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

### Is Catholic DSI free?

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

### Do MERS eTextbook or Catholic DSI have ads?

Neither MERS eTextbook nor Catholic DSI shows ads.

### Which is updated more often, MERS eTextbook or Catholic DSI?

MERS eTextbook ships an update every 3 months, and Catholic DSI every 8 months. Most recently, MERS eTextbook was updated on October 23, 2026 and Catholic DSI on October 26, 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.*