# O3 Alarm vs SmartAlarmsPro

The clearest difference is update cadence: SmartAlarmsPro at fortnightly against O3 Alarm's every 7 months. O3 Alarm's advantage is iOS requirement (7.0 vs 15). On price, ads, 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.

O3 Alarm ships an update every 7 months, SmartAlarmsPro fortnightly. The most recent releases landed on November 11, 2026 and November 12, 2026 respectively.

## The numbers

| Metric | O3 Alarm | SmartAlarmsPro |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/o3-alarm/id950579931/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 0.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 7 months | **Fortnightly** |
| Monetization | Free | — |
| Size | 71 MB | 201 MB |
| Requires iOS | **7.0** | 15 |
| Devices | iPhone, iPod | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Chuango Security Technology Corporation](https://appshunter.io/developer/534068551) | [瑞发 李](https://appshunter.io/developer/963471546) |

## What reviewers say

### O3 Alarm

[App page](https://appshunter.io/ios/app/o3-alarm/id950579931)

This security system app provides 360° protection for homes and small businesses. It allows remote monitoring, control of sensors, and customizable alerts for intrusions, floods, smoke, or gas. Manage your system, set routines, and receive notifications for enhanced safety and convenience.

**Highlights:** 360° protection with up to 50 wireless sensors, Intrusion, flood, smoke, and gas detection alerts, Customizable entry and exit delays, Adjustable siren duration and volume (up to 95 dB), Smartphone, remote control, and panel interaction, RFID tag management and SMS notifications, Supports multiple users and smartphones

**In-app purchases:** none


### SmartAlarmsPro

[App page](https://appshunter.io/ios/app/smartalarmspro/id6476841253)

**In-app purchases:** none


## Frequently asked questions

### Is O3 Alarm free?

O3 Alarm is free to download, with no in-app purchases.

### Is SmartAlarmsPro free?

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

### Do O3 Alarm or SmartAlarmsPro have ads?

Neither O3 Alarm nor SmartAlarmsPro shows ads.

### Which is updated more often, O3 Alarm or SmartAlarmsPro?

O3 Alarm ships an update every 7 months, and SmartAlarmsPro fortnightly. Most recently, O3 Alarm was updated on November 11, 2026 and SmartAlarmsPro on November 12, 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.*