A gadget is a thing
A gadget (a thing, Gizmo) is an article that is innovative and often cleverly designed. Often a gadget is a consumer electronics product (but it doesn't have to be). The technology or design is innovative, so a trendsetter likes to buy it. Often a gadget is also purchased as a status symbol. A gadget is especially interesting at the beginning (and even then it is more frequent for the entertainment purchased, and not so much for its functionality), later there are too many people who have it too, and it is not interesting anymore to have (or to show off). A gadget is often purchased online, in a special gadget or gift shop.