# F Numbers vs Lazmi AI

The clearest difference is in-app purchases: F Numbers at none against Lazmi AI's 10. Lazmi AI's advantage is update cadence (every 2 weeks vs every 13 months) and ratings volume (15 vs 3). On price, rating, ads and device support there is nothing between them.

Both are free to download. Lazmi AI sells 10 in-app purchases, starting at $3.99 per 7 days. F Numbers asks for nothing beyond the download.

On the App Store both sit at effectively the same score — 5.0 for F Numbers against 5.0 for Lazmi AI. That said, the two scores are not equally well evidenced: Lazmi AI has 15 ratings behind it against 3, so its average is the more settled of the two.

F Numbers ships an update every 13 months, Lazmi AI every 2 weeks. The most recent releases landed on November 1, 2026 and November 5, 2026 respectively.

## The numbers

| Metric | F Numbers | Lazmi AI |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [5.0 (3 ratings)](https://appshunter.io/ios/app/f-numbers/id929309069/reviews) | [5.0 (15 ratings)](https://appshunter.io/ios/app/lazmi-ai/id6757095309/reviews) |
| Number of ratings | 3 | **15** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 13 months | **Every 2 weeks** |
| Monetization | **Free** | Freemium |
| Size | 15 MB | 81 MB |
| Requires iOS | 13.0 | 13.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [ASMEIX CORPORATION](https://appshunter.io/developer/911716652) | [Lazmi.ai LLC](https://appshunter.io/developer/1864480515) |

## What reviewers say

### F Numbers

[App page](https://appshunter.io/ios/app/f-numbers/id929309069)

Quickly find filler metal groupings for welding procedures and performance qualifications. Access classifications with descriptions of intended use, based on ASME and AWS standards.

**Highlights:** Filler metal grouping lookup, Welding procedure qualification, Performance qualification data, Classification descriptions, ASME Section IX data, AWS standards data

**Features:** macOS Compatibility

**In-app purchases:** none


### Lazmi AI

[App page](https://appshunter.io/ios/app/lazmi-ai/id6757095309)

This app crafts emails and texts that sound authentically like you by learning your unique writing style. It offers modes for professional communication and casual conversations, ensuring your messages maintain your personal tone and phrasing.

**Highlights:** Learn and save personal writing styles, Generate emails in your voice, Reply to texts in your style, Pro Mode for professional emails, Fun Mode for dating and casual texts, History of generated content, Privacy-focused data handling

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

**In-app purchases (10)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Fun Mode Weekly | $3.99 | per 7 days |
| Pro Mode Weekly | $3.99 | per 7 days |
| Fun Mode Basic | $8.99 | per month |
| Pro Mode Basic | $8.99 | per month |
| Fun Mode Basic | $8.99 | per month |
| Pro Mode Basic | $8.99 | per month |
| Fun Mode Plus | $16.99 | per month |
| Pro Mode Plus | $16.99 | per month |
| Pro Mode Ultra | $34.99 | per month |
| Fun Mode Ultra | $49.99 | per month |


## Frequently asked questions

### Is F Numbers free?

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

### Is Lazmi AI free?

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

### Which has better reviews, F Numbers or Lazmi AI?

F Numbers and Lazmi AI are both rated 5.0 out of 5 on the App Store, from 3 and 15 ratings respectively.

### Do F Numbers or Lazmi AI have ads?

Neither F Numbers nor Lazmi AI shows ads.

### Which is updated more often, F Numbers or Lazmi AI?

F Numbers ships an update every 13 months, and Lazmi AI every 2 weeks. Most recently, F Numbers was updated on November 1, 2026 and Lazmi AI on November 5, 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.*