Apple Music has topped 10 million paying subscribers in its first six months, according to the Financial Times, a milestone that rival music-streaming service Spotify took nearly six years to reach.

The milestone comes less than two months after the service was extended to Google's Android operating system, the software that powers the majority of the world's mobile devices. Apple CEO Tim Cook said in October that more than 6.5 million people had signed up for the $10-a-month streaming music service that launched at the end of June. The service is also available in the UK for £10 a month and in Australia for AU$12.

Spotify, whose premium service costs the same as Apple Music in those three countries, counts 20 million paid members and another 75 million who listen for free. The London-based music streaming service launched in late 2008 and hit the 10 million subscriber mark in mid-2014.

Apple representatives declined to comment on the report.

Streaming music has exploded in popularity in recent years, with the number of on-demand streams in the US nearly doubling last year, according to researcher Nielsen's year-end music report. Fans logged nearly 145 billion audio streams in 2015, up 79 percent from the previous year, the researcher found.

Apple Music offers recommendations based on songs purchased from Apple's iTunes Store, ripped from CDs or chosen on-demand from an online catalog of more than 30 million titles. The service also includes a 24/7 radio station called Beats 1 and a service called Connect, where artists can talk to their fans and share songs directly to their iOS devices.

The service builds upon Beats Music, the music subscription service that Apple acquired in 2014 for $3 billion.

The introduction of Apple Music marked a radical departure from the norm for the electronics giant, which had for years resisted adopting a music subscription model for its customers.