Hi guys,
I’m working on an IoT application and I used to design the apps using MIT App inventor because I have an extension to make the app act as an MQTT client.
Recently after the updates that happen on Thunkable platform, there is no way to add custom extension.
Any suggestion to overcome this issue??
thank you in advance
Hi @bilal.mubdirx ,
Welcome to Thunkable community, MQTT extension is available on Thunkable classic only
http://community.thunkable.com/t/free-extension-mqtt-for-websocket-arduino-y-esp8266/3279
thank you so much, but my question was about Thunkable X.
OK, how can I use Thunkable Classic>>
Hi @bilal.mubdirx l, welcome to the community!! 
Like @davidsobhysabetb was saying above, it doesn’t work in thunkable X, only in the classic version. Unfortunately, classic is no longer available to new users. You could try AppInventor2 or learn React Native/Flutter. The latter are obviously much harder but will offer the most flexibility.
Hope that helps!
Can this extension be used in http://ai2.appinventor.mit.edu/ ?
Is Thunkabe classic still closed to new users?