I am currently successfully using a Droid Turbo with Letmobile and the corporate email app that is preloaded on the phone.
By going to the user console for the device and select advanced settings i show that my device's user agent is identified as User Agent: Android/5.1-EAS-2.0
I also have the width set to 100% and the height set to 4000px.
All check boxes are selected.
Try looking at these settings and see if they are comparable.
Unfortunately, it doesn't seem to work on this Motorola Droid Turbo. So I'm not sure why it works for Brett, but not for my end-user.
I got the following reply from support...
Please review this doc : https://community.landesk.com/support/docs/DOC-33248
This will assist with Hybrid mode and Motorola phones require it. I noticed that the doc doesn't mention Motorola and will be updating it.
I created the Hybrid policy, and the end-user can now read the email on the device. But this is not really desirable since the email message body is no longer protected/projected.