# iManifold vs Navisizer

The clearest difference is rating: iManifold at 3.1 against Navisizer's 2.4. iManifold also leads on review sentiment (50% vs 13%) and update cadence (every 3 weeks vs every 4 months). Navisizer's advantage is in-app purchases (none vs 10). On price, ratings volume, ads and device support there is nothing between them.

Both are free to download. iManifold sells 10 one-off in-app purchases. Navisizer asks for nothing beyond the download.

iManifold holds the better App Store score, 3.1 against 2.4. Both are backed by a comparable volume of ratings — 38 and 26 respectively. Written reviews point the same way: 50% of iManifold's written reviews are positive against 13% of Navisizer's.

iManifold ships an update every 3 weeks, Navisizer every 4 months. The most recent releases landed on October 12, 2026 and October 5, 2026 respectively.

## The numbers

| Metric | iManifold | Navisizer |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.1 (38 ratings)](https://appshunter.io/ios/app/imanifold/id784602842/reviews)** | [2.4 (26 ratings)](https://appshunter.io/ios/app/navisizer/id1327385997/reviews) |
| Number of ratings | **38** | 26 |
| Positive reviews | **50.0% of reviews** | 12.5% of reviews |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 3 weeks** | Every 4 months |
| Monetization | Free with in-app purchases | **Free** |
| Size | 29 MB | 21 MB |
| Requires iOS | **12.0** | 17.2 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [North Park Innovations Group, Inc.](https://appshunter.io/developer/595381427) | [Navien](https://appshunter.io/developer/1327385996) |

## What reviewers say

### iManifold

[App page](https://appshunter.io/ios/app/imanifold/id784602842)

This app calculates HVAC/R system performance and aids in troubleshooting. It offers a wide selection of refrigerants and equipment profiling for various common systems.

**Highlights:** Calculates HVAC/R system performance, Troubleshoots system problems, User input and live system data, Over 40 selectable refrigerants, Equipment profiling options, Customizable for common HVAC/R systems

**Features:** macOS Compatibility

**In-app purchases (10)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Charge & Airflow Report | $0.99 | one-time |
| Mechanical Inspection | $0.99 | one-time |
| Equipment Replacement Report | $0.99 | one-time |
| CSV Export | $0.99 | one-time |
| Annualized Savings Report | $0.99 | one-time |
| Gas Furnace Report | $0.99 | one-time |
| iManifold Report Pro - 1 Circuit | $1.99 | one-time |
| iManifold Report Pro - 2 Circuit | $2.99 | one-time |
| iManifold Report Pro - 3 Circuit | $3.99 | one-time |
| iManifold Report Pro - 4 Circuit | $4.99 | one-time |


### 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


## Frequently asked questions

### Is iManifold free?

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

### Is Navisizer free?

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

### Which has better reviews, iManifold or Navisizer?

iManifold is rated higher. iManifold averages 3.1 out of 5 from 38 ratings, while Navisizer averages 2.4 from 26 ratings.

### Do iManifold or Navisizer have ads?

Neither iManifold nor Navisizer shows ads.

### Which is updated more often, iManifold or Navisizer?

iManifold ships an update every 3 weeks, and Navisizer every 4 months. Most recently, iManifold was updated on October 12, 2026 and Navisizer on October 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.*