I am trying to get a siri/alexa app working, but i wonder if it responds to voice even if the phone is closed. Help plz
You would need to make use of an Extension that allows the App to run in the background.
We will change your Forum User Name - you cannot use a name that suggests you are an official member of MIT staff or represent the App Inventor software.
Not sure whether this approach still works...
Here is a google search of App Inventor and Alexa.
Here is a search of the community Search results for 'alexa' - MIT App Inventor Community
Perhaps some of interest is there ?
Use the SpeechRecognizer to command activities, go to a url etc. while the app is active using Blocks:
I am not aware of anything that will respond if your phone is turned off or sleeping. Chris' suggestion might work.