killer app
Noun
Meaning
killer app (plural killer apps)
(informal, computing) A killer application.
Examples
If you think about YouTube, YouTube is a 'searching the world's videos' problem, right? They all have to be there, but how do you find them? What I guess I'm trying to say is that search is still the killer app.
We want to reinvent the phone. What's the killer app? The killer app is making calls! It's amazing how hard it is to make calls on most phones. We want to let you use contacts like never before - sync your iPhone with your PC or mac.
As a technologist, I'm obsessed with searching for the next killer app.
So evidently music was a killer app and is a killer app for computer and the Internet; it just took the tech industry a long time to hear that message.