Is it appropriate to use the term "client" as an alternative to the word "application"?

Question

IT terminology

For example, the WhatsApp client instead of the WhatsApp application (because the second option has already been used in the previous few paragraphs).

Answer 1

The term "client" is commonly used when referring to an apparently existing client-server architecture. Thus, "client" and "application" are generally not synonymous, because "application" can be standalone. For example, a graphics editor or a calculator are, most often, applications, since they do not access any server or service. In the case of messengers, things are not so clear. Let's say, in the days of ICQ's popularity, it was perfectly normal to refer to the application that people used to communicate on ICQ as an "ICQ client". Most often, the admissibility of using the term "client" for messenger applications correlates with the openness of the protocol (as well as the presence of various implementations of both server software and client software using this protocol). For example, custom applications for working with the open Jabber protocol are often referred to as Jabber clients. And Skype, for which there are no alternative clients or alternative servers, is called the "Skype application". I emphasize that this is not a question of a strict definition, but an established practice.