# Sigma Office vs AI Email Writer

The clearest difference is in-app purchases: Sigma Office at none against AI Email Writer's 4. Sigma Office also leads on update cadence (every 3 weeks vs every 2 months). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. AI Email Writer sells 4 in-app purchases, starting at $3.99 per 7 days. Sigma Office asks for nothing beyond the download.

Sigma Office ships an update every 3 weeks, AI Email Writer every 2 months. The most recent releases landed on October 12, 2026 and September 29, 2026 respectively.

## The numbers

| Metric | Sigma Office | AI Email Writer |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[4.6 (21 ratings)](https://appshunter.io/ios/app/ai-email-writer-write-e-mail/id6449893552/reviews)** |
| Number of ratings | — | **21** |
| Positive reviews | — | 66.7% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 3 weeks** | Every 2 months |
| Monetization | — | Free with in-app purchases |
| Size | 81 MB | 14 MB |
| Requires iOS | 15.0 | 15.0 |
| Devices | iPhone, iPod | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Joaquin Guevara](https://appshunter.io/developer/1443082715) | [Speed Apps Labs LLP](https://appshunter.io/developer/1681161383) |

## What reviewers say

### Sigma Office

[App page](https://appshunter.io/ios/app/sigma-office/id1533340093)

**In-app purchases:** none


### AI Email Writer

[App page](https://appshunter.io/ios/app/ai-email-writer-write-e-mail/id6449893552)

This AI-powered app assists users in crafting professional and compelling emails quickly. It offers intelligent suggestions for content, tone, and style, integrates with popular email services, and includes grammar and spell check for error-free communication.

**Highlights:** AI email generation, Productivity enhancement, Professional email quality, Personalized assistance, Gmail/Outlook/Hotmail integration, Email templates, Grammar and spell check

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

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium Weekly | $3.99 | per 7 days |
| Premium Half-Yearly | $14.99 | per 6 months |
| Premium Yearly | $17.99 | per year |
| Premium Lifetime | $39.99 | one-time |


## Frequently asked questions

### Is Sigma Office free?

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

### Is AI Email Writer free?

AI Email Writer is free to download, with in-app purchases available.

### Do Sigma Office or AI Email Writer have ads?

Neither Sigma Office nor AI Email Writer shows ads.

### Which is updated more often, Sigma Office or AI Email Writer?

Sigma Office ships an update every 3 weeks, and AI Email Writer every 2 months. Most recently, Sigma Office was updated on October 12, 2026 and AI Email Writer on September 29, 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.*