# Co vs ERSB Lite

The clearest difference is rating: ERSB Lite at 4.0 against Co's 2.6. ERSB Lite also leads on update cadence (every 2 months vs every 4 months). Co's advantage is in-app purchases (none vs 5) and ratings volume (17 vs 3). On price and ads there is nothing between them.

Both are free to download. ERSB Lite sells 5 one-off in-app purchases. Co asks for nothing beyond the download.

ERSB Lite holds the better App Store score, 4.0 against 2.6. That said, the two scores are not equally well evidenced: Co has 17 ratings behind it against 3, so its average is the more settled of the two. Written reviews complicate that: 8% of Co's written reviews are positive against 0% of ERSB Lite's, so the app with the better star average is not the one people write more warmly about.

Co ships an update every 4 months, ERSB Lite every 2 months. Both last shipped on November 1, 2026.

## The numbers

| Metric | Co | ERSB Lite |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [2.6 (17 ratings)](https://appshunter.io/ios/app/cowriter-universal/id915105799/reviews) | **[4.0 (3 ratings)](https://appshunter.io/ios/app/ersb-lite/id976322567/reviews)** |
| Number of ratings | **17** | 3 |
| Positive reviews | **8.3% of reviews** | 0.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 4 months | **Every 2 months** |
| Monetization | **Free** | Free with in-app purchases |
| Size | 45 MB | 253 MB |
| Requires iOS | **10.0** | 13.0 |
| Devices | **iPhone, iPad, iPod** | iPad |
| Age rating | 4+ | 4+ |
| Developer | [Don Johnston Incorporated](https://appshunter.io/developer/674099735) | [Attainment Company](https://appshunter.io/developer/403989333) |

## What reviewers say

### Co

[App page](https://appshunter.io/ios/app/cowriter-universal/id915105799)

This app provides advanced word prediction and spelling support for students. It offers grammar-smart suggestions and access to millions of topic-specific dictionaries to aid in writing. Built-in text-to-speech functionality helps users review their work.

**Highlights:** Grammar-smart word prediction, Millions of topic-specific dictionaries, Flexspell™ technology for spelling errors, Built-in text-to-speech, Personalized vocabulary and settings

**Features:** macOS Compatibility

**In-app purchases:** none


### ERSB Lite

[App page](https://appshunter.io/ios/app/ersb-lite/id976322567)

This app builds early reading skills for students progressing from foundational literacy. It uses systematic instruction and assessments to help individuals read independently, proving effective for those with intellectual disabilities and autism.

**Highlights:** Early literacy skill development, Systematic instruction, Ongoing assessments, Progress to 2nd-grade reading level, Effective for intellectual disabilities, Effective for autism

**In-app purchases (5)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Levels 12-16 | $29.99 | one-time |
| Levels 17-21 | $29.99 | one-time |
| Levels 22-26 | $29.99 | one-time |
| Levels 2-6 | $29.99 | one-time |
| Levels 7-11 | $29.99 | one-time |


## Frequently asked questions

### Is Co free?

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

### Is ERSB Lite free?

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

### Which has better reviews, Co or ERSB Lite?

ERSB Lite is rated higher. Co averages 2.6 out of 5 from 17 ratings, while ERSB Lite averages 4.0 from 3 ratings.

### Do Co or ERSB Lite have ads?

Neither Co nor ERSB Lite shows ads.

### Which is updated more often, Co or ERSB Lite?

Co ships an update every 4 months, and ERSB Lite every 2 months. Most recently, Co was updated on November 1, 2026 and ERSB Lite on November 1, 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.*