"Application" is a general term that doesn't necessarily mean "client"—it can refer to a client-less service, i.e., just a server—, though it's understandable, given the colloquial usage of the term "app" that you used it this way.
Stick to the term "client" when speaking about the front-end of anything.
"Application" is a general term that doesn't necessarily mean "client"—it can refer to a client-less service, i.e., just a server—, though it's understandable, given the colloquial usage of the term "app" that you used it this way.
Stick to the term "client" when speaking about the front-end of anything.