I would like to fetch records from a separate application. Here is an example:

ApplicationA: 

"Form1" has fields: Name1, Email1, Department1 

ApplicationB:

"Form2" has fields: Name2 and Email2

--> Name2 is my lookup field. 

--> When I lookup a name, I want Email2 to automatically populate from Application A field Email1. 

How do I do this? Please give me an example.

Thank you.