# Fix Grammar vs Underlayer

The clearest difference is ads: Fix Grammar at none against Underlayer's shown. On price, update cadence, in-app purchases and device support there is nothing between them.

Both are free to download. Fix Grammar sells 2 in-app purchases, starting at $0.99 per month and Underlayer sells 1 in-app purchase, starting at $2.99 per 7 days. Whichever you choose, the download price is not the number that matters.

Fix Grammar ships an update every 9 months, Underlayer every 5 months. The most recent releases landed on September 29, 2026 and September 12, 2026 respectively.

## The numbers

| Metric | Fix Grammar | Underlayer |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/fix-grammar/id6468834867/reviews)** | — |
| Number of ratings | **1** | — |
| In-app purchases | Yes | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 9 months | **Every 5 months** |
| Monetization | Freemium | — |
| Size | 9 MB | 169 MB |
| Requires iOS | 15.6 | **15.1** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Ashen Ishanka Costha](https://appshunter.io/developer/1566497857) | [Mihail Rukavishnikov](https://appshunter.io/developer/1648782212) |

## What reviewers say

### Fix Grammar

[App page](https://appshunter.io/ios/app/fix-grammar/id6468834867)

This app helps users identify and correct grammar errors in their writing. It aims to improve text quality for students, professionals, and casual writers, making writing polished and error-free.

**Highlights:** Grammar correction, Error spotting, Text polishing, Professional writing enhancement, User-friendly interface

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly Premium | $0.99 | per month |
| Yearly Premium | $9.99 | per year |


### Underlayer

[App page](https://appshunter.io/ios/app/underlayer/id6753363956)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium | $2.99 | per 7 days |


## Frequently asked questions

### Is Fix Grammar free?

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

### Is Underlayer free?

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

### Do Fix Grammar or Underlayer have ads?

Underlayer shows ads; Fix Grammar does not.

### Which is updated more often, Fix Grammar or Underlayer?

Fix Grammar ships an update every 9 months, and Underlayer every 5 months. Most recently, Fix Grammar was updated on September 29, 2026 and Underlayer on September 12, 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.*