An application when used in the way usually refers to a piece of software. If it doesn't mean that I don't know what it means. Perhaps the writer means techniques or disciplines. I don't know that devices are ever called applications, although they may be called appliances.
What does the writer say next? I would be expecting some example or explanation to follow. The question is a little short on context and background.
It still seems to me that the writer is using the wrong word and means something like "disciplines" in the sense of "fields of study". I can't see any dictionary definition that would apply in the way he or she has used the word (as I said, unless it was a computer software application, which seems unlikely).