Shazam was one of the first third-party applications available on the iPhone, as it launched in 2008 alongside the iOS App Store. Later that year, it arrived on Android, and it has continued to maintain a strong userbase. According to a report from TechCrunch, Apple could be looking to buy Shazam as soon as Monday.
If you're not familiar with the app, it uses your phone's microphone to listen to music currently playing, and give you information about it (and links to buy it). Shazam passed one billion downloads across all platforms back in September 2016. The company made £40.3 million in revenue during the 2016 fiscal year, with the CEO indicating that he wanted Shazam to be an acquisition target.
Shazam has also been experimenting with augmented reality, which could be the reason Apple is looking to buy it. The service is already integrated into Apple's Siri voice assistant, similar to the "What's this song" command in Google Now/Assistant.