This is an MQTT client and test tool. MQTT is a machine-to-machine (M2M) messaging protocol commonly used for IoT applications. For more information on MQTT visit

MQTTool can connect to authenticated and unauthenticated MQTT brokers, subscribe to topics, and publish messages to topics.

I built this tool as i was doing my own MQTT investigations and I've posted it hoping others would find it useful too. I continue to use it on projects, and I'm continuing to look to improve this tool. If there are changes that would make this more useful, please send me feedback. Thanks!

What’s New

Version 2.6

MQTTool source has been released on GitHub.
See for more details.

This update includes some minor layout fixes.

Ratings and Reviews

4.5 out of 5
21 Ratings

21 Ratings

Ed_111 ,

Works great.

You need to push on the text in the body of the page for both “connect” and “publish” rather than below on the menu bar. These could be highlighted or a different color and In bold to make it a little nicer. But it works great! I tried it for publishing and subscribing to a Mosquitto MQTT broker on a Raspberry Pi and had no troubles. Great app.

SoftJunkie ,

Does the job

I was looking for an iOS client to use for my Arduino experiments. I was able to interact with my Arduino device within 10 minutes of downloading this app. Very handy.

Sardjono ,

Handy utility, although UI a bit confusing

I was spending a but of time checking my mqtt broker until I finally realized I need to tap on the “connect” text in the main window instead of the “connect” icon at the bottom left of the screen 😳

Once that was sorted out the app works nicely 👍


Brent Petit
18.7 MB

Requires iOS 10.0 or later. Compatible with iPhone, iPad, and iPod touch.



Age Rating


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

You May Also Like