Broker profiles & templates
Save your brokers with ready-made templates for Mosquitto, Home Assistant, Zigbee2MQTT and AWS IoT. You get one profile free and more with Pro, and the app reconnects with backoff when the network changes.
Native for iOS & iPadOS
Debug any MQTT broker right from your iPhone
MQTT Commander is a professional MQTT client and debugger for iPhone and iPad. Connect to Mosquitto, Home Assistant, Zigbee2MQTT or AWS IoT, inspect every payload, and find out why a connection fails.
Free · Pro unlock $4.99, one-time
MQTT 3.1.1 & 5.0TLS · mTLS · WebSocketPrivate by defaultFree to download
MQTT 3.1.1 & 5.0
Full protocol support
QoS 0 · 1 · 2
Every delivery guarantee
TCP · TLS · WS · WSS
All transports, including mTLS
On-device
Your broker data never leaves your iPhone
Connection Doctor
Know exactly why a connection failed
Most clients report “connection failed” and stop there. MQTT Commander walks the connection one stage at a time and names the step that broke, with a plain-language cause and a suggested fix.
- Input: Host, port and URI validated
- DNS: Name resolved to an address
- TCP: Socket opened to the broker (WSS upgrade included)
- TLS: Handshake completed; ALPN & SNI negotiated
- Certificate: Chain, expiry and hostname checked
- MQTT: CONNACK reason code read
- Auth: Credentials accepted by the broker
- Pinpoints the failing stage: DNS, TCP, TLS, certificate, ALPN/SNI or MQTT
- Explains TLS handshake errors: expired certificate, hostname mismatch, wrong ALPN
- Privacy-safe diagnostics: secrets and private hostnames never hit the log
- Reads MQTT 5 reason codes so auth and packet-size failures are obvious
Certificate Manager
TLS and mTLS without the guesswork
Import a CA as PEM and your client identity as a .p12/.pfx bundle, and MQTT Commander checks the certificate's expiry and hostname, then keeps every secret in the iOS Keychain.
- Import the CA as PEM and the client identity as a .p12/.pfx bundle, with passphrase support
- Checks the certificate's expiry and flags SAN/CN and hostname mismatches
- ALPN protocol list (incl. AWS IoT x-amzn-mqtt-ca) and SNI override
- SHA-256 fingerprints; client certs and keys stored in the Keychain
Video walkthrough
Watch MQTT Commander find a TLS failure
83 seconds in the app: browse a live topic tree, read parsed JSON, publish with QoS and retain, then run Connection Doctor on a broker that fails its TLS check.
Features
Everything you need to work with MQTT
A full debugging toolkit, built mobile-first for the way you work.
MQTT 3.1.1 & 5.0
Full MQTT 5 properties, QoS 0/1/2, retained messages, Last Will, wildcard and shared subscriptions, over TCP, TLS, WebSocket or WSS.
Payload Inspector
Pretty-print and syntax-highlight JSON, diff two payloads, decode hex and Base64, preview images, and copy any value by JSONPath.
Topic tree & smart-home presets
Browse the whole broker or jump straight to homeassistant/# and zigbee2mqtt/#. Retained markers, regex filtering, and built to handle thousands of topics.
Safe publish composer
Draft-first publishing with QoS, a retain warning, explicit retained-delete confirmation, reusable templates and safe home-automation presets.
Message log & export
Filter traffic by topic, payload, direction, QoS or errors, then export to CSV or JSON, with secrets and raw payloads redacted.
Privacy-first
Your brokers stay yours
Connections, topics, payloads, credentials and certificates stay on your device and never reach our servers. The app sends only anonymous, optional diagnostics, which you can switch off in Settings.
- No account, no sign-in
- Your broker data never leaves your device
- No ads, never sold or shared
- Secrets stored in the iOS Keychain
- Anonymous crash & usage stats you can turn off
Why MQTT Commander
Other MQTT clients are desktop-bound or bare-bones viewers. This one debugs from your phone.
Typical MQTT clients
- A connection “fails” and the reason stays hidden
- Certificate setup is pure trial-and-error
- Desktop-only, or a thin read-only mobile viewer
- Send anything, including accidental retained writes
- Your data synced through someone else's cloud
MQTT Commander
- Connection Doctor names the failing stage and the fix
- Certificate Manager checks certificate expiry, hostname, ALPN and SNI
- Native iPhone & iPad app, designed for touch
- Draft-first publishing with retained-delete confirmation
- Your broker data never leaves your device
A closer look
Real screens from the app.
Smart-home topics at a glance
Frequently asked questions
Which MQTT versions does it support?
Both MQTT 3.1.1 and MQTT 5.0, including full MQTT 5 properties, QoS 0/1/2, retained messages, Last Will, and wildcard and shared subscriptions.
Can it connect over TLS and mTLS?
Yes. Plain TCP, TLS, WebSocket and secure WebSocket are all supported. The Certificate Manager imports a CA as PEM and your client identity as a .p12/.pfx bundle, checks the certificate's expiry and hostname, and supports ALPN and SNI overrides for setups like AWS IoT Core.
Does it work with Home Assistant and Zigbee2MQTT?
Yes. There are built-in presets for homeassistant/# and zigbee2mqtt/#, plus safe command templates for common actions like permit_join and restart.
Is any of my data sent anywhere?
Connections, topics, payloads and credentials stay on your device and never reach us. The app does send anonymous crash and usage diagnostics (via Sentry and Aptabase) to help us improve it, with no personal data and no cross-app tracking, and you can turn it off in Settings.
Is it a subscription?
No. The app is free to download, and Pro is a one-time $4.99 unlock you keep for good. No subscription, no ads.
What devices are supported?
iPhone and iPad running iOS 17 or later. The interface is native SwiftUI and adapts to both.
Put a real MQTT debugger in your pocket
Connect, inspect, publish and diagnose, from the broker on your bench to mTLS endpoints in the field.
Free · Pro unlock $4.99, one-time
Free to downloadNo subscription, no adsPrivate by defaultiPhone & iPad