External Link to PowerApps Screen - URL for email bodies.

*****UPDATE*****************

OK so Microsoft launched the "StartScreen" in PowerAPPs. The below instructions do not work anymore.

Click here for updated instructions.

There's some documentation on this that has the wrong syntax using a "?" but the correct operator is "&".  At least in my system....

The correct syntax for the url is:

https://apps.powerapps.com/play/52e8bcfb-4fd6-41f1-bc1a-971a2fc7a555?ten...&ScreenName=1

Find this part of the URL in your Apps details > https://apps.powerapps.com/play/52e8bcfb-4fd6-41f1-bc1a-971a2fc7a555?ten...

Then add the parameter to the end on the url " &ScreenName=1 "

Add the following to your App's OnStart variable

" If(Param("ScreenName") = "1",Navigate(YourScreenName),Navigate(HomeScreen)) "

If the parameter "Screen=1" doesn't exist in the URL then the app will direct the user to the "HomeScreen" :)

In my case, when the app creates a new record, the platform send an email to the IT department letting the know a New Employee has started and need Network Permissions.  The email notification sent has a link to a screen where IT can see all the New Hires that need account set - up. :)