Activity starter E-mail working in companion/ not working in app

I am writing a little app, that enters things in a list and then sends the items of the list to a mail recipient.

so I set up an activity starter.

And...it works fine as long as I am using the AIcompanion.

When I load the app to my phone (sony xperia 2; android 5.1) it does not work.

can anyone tell me why?

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See Taifun's post HERE on different email solutions.

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