# Sub vs Ion Blue

The clearest difference is rating: Sub at 4.4 against Ion Blue's 2.0. Sub also leads on ratings volume (786 vs 8). Ion Blue's advantage is monetization model (free vs ad-supported) and review sentiment (25% vs 15%). On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Sub holds the better App Store score, 4.4 against 2.0. That said, the two scores are not equally well evidenced: Sub has 786 ratings behind it against 8, so its average is the more settled of the two. Written reviews complicate that: 15% of Sub's written reviews are positive against 25% of Ion Blue's, so the app with the better star average is not the one people write more warmly about.

Sub ships an update every 5 weeks, Ion Blue every 2 months. Both last shipped on October 24, 2026.

## The numbers

| Metric | Sub | Ion Blue |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.4 (786 ratings)](https://appshunter.io/ios/app/sub-zero-group-owners-app/id1248991284/reviews)** | [2.0 (8 ratings)](https://appshunter.io/ios/app/ion-blue/id6469643514/reviews) |
| Number of ratings | **786** | 8 |
| Positive reviews | 14.7% of reviews | **25.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 5 weeks** | Every 2 months |
| Monetization | Ad-supported | **Free** |
| Size | 69 MB | 56 MB |
| Requires iOS | 15.5 | 15.5 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Sub-Zero and Wolf](https://appshunter.io/developer/983988992) | [Metropolitan Industries, Inc.](https://appshunter.io/developer/1476515241) |

## What reviewers say

### Sub

[App page](https://appshunter.io/ios/app/sub-zero-group-owners-app/id1248991284)

This app enhances your kitchen experience by guiding you through recipes from websites and a curated collection. It allows remote control and monitoring of Sub-Zero refrigeration, Cove dishwashing, and Wolf appliances, ensuring optimal performance and convenience.

**Highlights:** Guided cooking from online recipes, Chef-tested recipes optimized for Wolf appliances, Remote dishwasher control and monitoring, Refrigerator settings and alerts, Filter recipes by cooking mode, Bookmark and share recipes

**Features:** Vision Pro support

**In-app purchases:** none

**What reviewers like**

- 🚀 Responsive and intuitive app
- 👍 Helpful notifications and alerts
- 🔒 Secure connection to appliances

**What reviewers complain about**

- 🐛 Frequent connection issues and disconnects
- 🔍 Lack of actual temperature monitoring
- 🤔 Confusing setup and pairing process
- 🔍 Missing key features like remote start

**Reported bugs**

- App crashes after recent updates
- Unable to log in or register account
- Appliances disappear from the app
- Firmware update failures brick appliances

**Requested features**

- Add support for Celsius temperature units
- Provide real-time temperature and energy consumption data
- Integrate with smart home platforms like Apple HomeKit


### Ion Blue

[App page](https://appshunter.io/ios/app/ion-blue/id6469643514)

Monitor and manage your smart home plumbing system remotely. Receive custom alerts for potential issues like flooding or water damage, and grant access to trusted contacts for timely response. Ideal for homeowners and property managers seeking peace of mind.

**Highlights:** Remote plumbing system monitoring, Flood and water damage alerts, Customizable push notifications, Multi-user access with permissions, Support for multiple residences, Cloud-enabled solutions

**In-app purchases:** none


## Frequently asked questions

### Is Sub free?

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

### Is Ion Blue free?

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

### Which has better reviews, Sub or Ion Blue?

Sub is rated higher. Sub averages 4.4 out of 5 from 786 ratings, while Ion Blue averages 2.0 from 8 ratings.

### Do Sub or Ion Blue have ads?

Neither Sub nor Ion Blue shows ads.

### Which is updated more often, Sub or Ion Blue?

Sub ships an update every 5 weeks, and Ion Blue every 2 months. Most recently, Sub was updated on October 24, 2026 and Ion Blue on October 24, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*