# Sec MQTT Pub vs Double memo

The clearest difference is ads: Sec MQTT Pub at none against Double memo's shown. Double memo's advantage is update cadence (every 2 weeks vs every 28 months). On price, in-app purchases, device support and iOS requirement there is nothing between them.

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

Sec MQTT Pub ships an update every 28 months, Double memo every 2 weeks. The most recent releases landed on October 10, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | Sec MQTT Pub | Double memo |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/sec-mqtt-pub/id1554992163/reviews)** | — |
| Number of ratings | **1** | — |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | Every 28 months | **Every 2 weeks** |
| Monetization | Free | — |
| Size | 3 MB | 37 MB |
| Requires iOS | **14.0** | 15.8.3 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Care Active Corp.](https://appshunter.io/developer/1739001802) | [Hideaki Uchikoshi](https://appshunter.io/developer/1559575002) |

## What reviewers say

### Sec MQTT Pub

[App page](https://appshunter.io/ios/app/sec-mqtt-pub/id1554992163)

This app provides a secure MQTT client for communicating with IoT devices using X.509 authentication and AES-128 encryption. It allows for customized messages and topics, offering a robust solution for secure IoT project communication.

**Highlights:** X.509 authentication, Root CA authentication support, AES-128 encryption, Face ID / Touch ID support, Customizable buttons for messages and topics, Open-source project

**In-app purchases:** none


### Double memo

[App page](https://appshunter.io/ios/app/double-memo/id6502283245)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Sec MQTT Pub free?

Sec MQTT Pub is free to download, with no in-app purchases.

### Is Double memo free?

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

### Do Sec MQTT Pub or Double memo have ads?

Double memo shows ads; Sec MQTT Pub does not.

### Which is updated more often, Sec MQTT Pub or Double memo?

Sec MQTT Pub ships an update every 28 months, and Double memo every 2 weeks. Most recently, Sec MQTT Pub was updated on October 10, 2026 and Double memo on October 25, 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.*