# Navisizer vs My Main AI

The clearest difference is review sentiment: My Main AI at 67% against Navisizer's 13%. My Main AI also leads on rating (4.2 vs 2.4) and update cadence (weekly vs every 4 months). Navisizer's advantage is in-app purchases (none vs 3) and ratings volume (26 vs 5). On price, ads and device support there is nothing between them.

Both are free to download. My Main AI sells 3 in-app purchases, starting at $19.99 per month. Navisizer asks for nothing beyond the download.

My Main AI holds the better App Store score, 4.2 against 2.4. That said, the two scores are not equally well evidenced: Navisizer has 26 ratings behind it against 5, so its average is the more settled of the two. Written reviews point the same way: 13% of Navisizer's written reviews are positive against 67% of My Main AI's.

Navisizer ships an update every 4 months, My Main AI weekly. The most recent releases landed on October 22, 2026 and October 13, 2026 respectively.

## The numbers

| Metric | Navisizer | My Main AI |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [2.4 (26 ratings)](https://appshunter.io/ios/app/navisizer/id1327385997/reviews) | **[4.2 (5 ratings)](https://appshunter.io/ios/app/my-main-ai/id6739449919/reviews)** |
| Number of ratings | **26** | 5 |
| Positive reviews | 12.5% of reviews | **66.7% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 4 months | **Weekly** |
| Monetization | **Free** | Free with in-app purchases |
| Size | 21 MB | 53 MB |
| Requires iOS | 17.2 | **15.1** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Navien](https://appshunter.io/developer/1327385996) | [Unome LLC](https://appshunter.io/developer/1651096905) |

## What reviewers say

### Navisizer

[App page](https://appshunter.io/ios/app/navisizer/id1327385997)

This app helps size domestic hot water heating systems for residential and commercial use. It calculates operating costs, savings, and generates comprehensive job specifications for Navien NPE Series tankless water heaters.

**Highlights:** Residential system sizing, Operating cost and savings calculation, Commercial application sizing (ASHRAE Hunter Curve), Tankless and tankless with storage solutions, Comprehensive job specification output, Save, print, or email system specs

**Features:** macOS Compatibility

**In-app purchases:** none


### My Main AI

[App page](https://appshunter.io/ios/app/my-main-ai/id6739449919)

This AI-powered platform offers a suite of tools to enhance productivity and creativity. Generate content, create images, produce voiceovers, and manage communications efficiently. It's designed for accessibility and ethical AI practices.

**Highlights:** AI Assistants for daily tasks, AI-powered content generation, AI image creation, AI voiceovers, Bulk SMS and email services, Marketing solutions

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| MyMainAI Pro Plans | $19.99 | per month |
| MyMainAI Pro | $29.99 | per month |
| MyMainAI Elite | $99.99 | per month |


## Frequently asked questions

### Is Navisizer free?

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

### Is My Main AI free?

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

### Which has better reviews, Navisizer or My Main AI?

My Main AI is rated higher. Navisizer averages 2.4 out of 5 from 26 ratings, while My Main AI averages 4.2 from 5 ratings.

### Do Navisizer or My Main AI have ads?

Neither Navisizer nor My Main AI shows ads.

### Which is updated more often, Navisizer or My Main AI?

Navisizer ships an update every 4 months, and My Main AI weekly. Most recently, Navisizer was updated on October 22, 2026 and My Main AI on October 13, 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.*