# Occu vs ATC CALA

The clearest difference is rating: Occu at 4.4 against ATC CALA's 2.0. Occu also leads on ads (none vs shown) and monetization model (free vs ad-supported). ATC CALA's advantage is update cadence (every 6 weeks vs every 9 months) and review sentiment (50% vs 25%). On price, in-app purchases and device support there is nothing between them.

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

Occu holds the better App Store score, 4.4 against 2.0. That said, the two scores are not equally well evidenced: Occu has 7 ratings behind it against 1, so its average is the more settled of the two. Written reviews complicate that: 25% of Occu's written reviews are positive against 50% of ATC CALA's, so the app with the better star average is not the one people write more warmly about.

Occu ships an update every 9 months, ATC CALA every 6 weeks. The most recent releases landed on October 24, 2026 and October 13, 2026 respectively.

## The numbers

| Metric | Occu | ATC CALA |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.4 (7 ratings)](https://appshunter.io/ios/app/occu/id1550336460/reviews)** | [2.0 (1 ratings)](https://appshunter.io/ios/app/atc-cala/id1588090783/reviews) |
| Number of ratings | **7** | 1 |
| Positive reviews | 25.0% of reviews | **50.0% of reviews** |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | Every 9 months | **Every 6 weeks** |
| Monetization | **Free** | Ad-supported |
| Size | 59 MB | 17 MB |
| Requires iOS | **12.0** | 14.6 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Yardi Systems, Inc.](https://appshunter.io/developer/425728804) | [Ferroli España](https://appshunter.io/developer/1450809350) |

## What reviewers say

### Occu

[App page](https://appshunter.io/ios/app/occu/id1550336460)

Manage your apartment living experience with ease. Pay rent, submit maintenance requests with media, reserve amenities, and stay connected with your community. Track package deliveries and even renew your lease directly within the app.

**Highlights:** Arrange rent payments, Submit maintenance requests, Reserve community amenities, Track package deliveries, Community message board, Lease renewal

**Features:** macOS Compatibility, Apple Wallet

**In-app purchases:** none


### ATC CALA

[App page](https://appshunter.io/ios/app/atc-cala/id1588090783)

Control your new ATC thermal emitters remotely. Adjust settings, monitor performance, and manage your heating system from your smartphone. Designed for efficient and convenient home climate management.

**Highlights:** Remote control of thermal emitters, Adjust settings, Monitor performance, Manage heating system, Smartphone integration

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Occu free?

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

### Is ATC CALA free?

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

### Which has better reviews, Occu or ATC CALA?

Occu is rated higher. Occu averages 4.4 out of 5 from 7 ratings, while ATC CALA averages 2.0 from 1 ratings.

### Do Occu or ATC CALA have ads?

ATC CALA shows ads; Occu does not.

### Which is updated more often, Occu or ATC CALA?

Occu ships an update every 9 months, and ATC CALA every 6 weeks. Most recently, Occu was updated on October 24, 2026 and ATC CALA 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.*