The London-based Shazam boasts more than 100 million monthly users, and hit one billion total downloads previous year.
Shazam's music recognition feature is already integrated with Apple's Siri voice assistant.
Apple said it would use Shazam and its development team to beef up Apple Music, the streaming subscription service that is No. 2 to Spotify.
Shazam is used to discover music, by using the smartphone microphone to identify songs. Shazam would allow Apple Music to increase its market share by making it simpler for users to identify songs.
Apple did not give a price for the acquisition. With today's acquisition, Shazam should continue to drive traffic to Apple Music without the need to sustain itself as a standalone business.
Shazam now has over 100 million users worldwide.
The US technology giant isn't revealing its motivations beyond saying that it has "exciting plans in store".
Back in 2015 the company was valued at 1.2 Billion dollars and has since maintained around 1 billion downloads per day. It, therefore, makes ideal sense that if anyone was going to buy Shazam, it was going to be Apple.
Perhaps some of Shazam's audio-recognition technology might provide a quick fix, or at the very least Apple might believe it could add extra capabilities in the future.
With Apple's HomePod smart speaker in competition amongst AI assisstants, Apple may gain a competitive edge through the deal.
So why would Apple be interested in Shazam, even if it is a unicorn at a cut price? The show, which has contestants trying to beat the company's app in recognizing songs, first aired in May, and has been renewed for a second season. Shazam is Apple's answer to Spotify's Echo Nest.