Turn off tablet

I have to create an app that requires that by pressing a button, turn off the tablet.

How can I do?

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try the activity starter and this solution http://stackoverflow.com/a/24700240/1545993

Taifun

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How to do with app inventor 2?

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as already said, use the activity starter

see also App Inventor Activity Starter App with more than 100 examples of activities

and several examples here https://puravidaapps.com/snippets.php#2activity

now it's your turn

A very good way to learn App Inventor is to read the free Inventor's Manual here in the AI2 free online eBook   http://www.appinventor.org/book2 ... the links are at the bottom of the Web page.  The book 'teaches' users how to program with AI2 blocks.

There is a free programming course here http://www.appinventor.org/content/CourseInABox/Intro  and the aia files for the projects in the book are here:  http://www.appinventor.org/bookFiles  

How to do a lot of basic things with App Inventor are described here:  http://www.appinventor.org/content/howDoYou/eventHandling  .

Also do the tutorials http://appinventor.mit.edu/explore/ai2/tutorials.html to learn the basics of App Inventor, then try something and follow the

 Top 5 Tips: How to learn App Inventor

You will not find a tutorial, which does exactly what you are looking for. But doing the tutorials (not only reading a little bit) help you to understand, how things are working. This is important and this is the first step to do.

Taifun

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