Hi DJI forum!
I am new to the "drone world" and hope someone here can help me out. I work for a land trust and we have begun using our DJI Phantom Vision + to monitor properties deep in the desert. Our properties are all mapped and exist on a map layer. Is there any app that can be used as a flight manager/ground station with the capability to import/overlay custom layers to the standard map? With this functionality, I could then set up a flight plan to scan the property.
Help?

short answer is -  no.

"No" is no good. Anyone interested in helping a non profit create this tool??

We can compensate with $$!

Bump. Anyone interested in tackling a project like this??

Try contacting Trimble:

http://www.trimble.com/Corporate/About_Locations.aspx
They manufacture professional survey equipment and also sell fixed wing UAVs.

They may be able to help or perhaps :
Pix4D software developers
https://pix4d.com

Surely what you do is create Ground Control Points around the various properties, do an automated flight using perhaps a grid flight path  with a minimum of 5 Control Points fixed around teh property site, then input the specific coordinates of the Ground Control Points previous recorded into the software.  You should be able to overlay the aerial photography or import into CAD etc. onto a known map.  

Contact the above links for further help.  
Also check out Agisoft software  who also produce a software for collection of geospatial data to produce 3D models  - same as Pix4D

Good luck