You may want to find out why no one uses the EMR app.
As an IT professional, I can tell you that making an assumption as to why someone does not use an application is just that - an assumption.
The app may not be intuitive, user friendly, or provide the user with the functionality that he needs when compared to a fully developed and integrated desktop application.
It also sounds like your purchasing mechanism needs re-evaluation. We would require a written justification from the requestor, approval from department head, IT department head, and Purchasing / Finance for any IT related purchases.
I always follow up with the requestor when they have had some time to use a new device. "How is it working out?" "I haven't seen it on the network in X weeks." "I have noticed that you have not accessed the EMR app in X weeks. Do you need help?" etc.
If they know you have monitoring tools, they usually smarten up.