This app was mentioned in 8 comments, with an average of 2.50 upvotes
You can download a kiosk app from the play store or create your own kiosk mode.
Kiosk app: https://play.google.com/store/apps/details?id=com.gears42.surelock&hl=en
Create your own: http://www.andreas-schrade.de/2015/02/16/android-tutorial-how-to-create-a-kiosk-mode-in-android/
If anybody's curious about Surelock, I found it on the play store. It has $66 in in-app purchases, which I assume is how they unlock the full version.
Maybe look at something like this? Same principle as the Honeywell launcher:
https://play.google.com/store/apps/details?id=com.gears42.surelock
Warehouse devices should mostly maintain a fairly static configuration which makes an MDM solution overkill if you just want to lock the device down.
If I understand your problem correctly, you need something like this - https://play.google.com/store/apps/details?id=com.gears42.surelock&hl=en
But, even for that to work, your phone needs to stay powered on till you install the app and get into it's settings.
Your best bet would be to manually unjam the power button with the help of someone experienced.
Kiosk apps allow you to selectively lock features on android tablets https://play.google.com/store/apps/details?id=com.gears42.surelock&hl=en
This might be what you are looking for
https://play.google.com/store/apps/details?id=com.gears42.surelock
I don't know about the screen, but this claims it can block hardware keys