Spotify is trying to raise awareness around the fact that it's cheaper to subscribe on the web instead of through Apple's App Store. The leading subscription music service plans to email iPhone customers the below note encouraging them, if they haven't already, to start paying at Spotify.com and save a few dollars. "In case you didn’t know, the normal Premium price is only $9.99, but Apple charges 30 percent on all payments made through iTunes," the email blast reads. "You can get the exact same Spotify for only $9.99/month, and it’s super simple."

The message is followed with a step-by-step tutorial that explains how to shut off auto-renew through iTunes (so Apple won't keep charging you the higher $12.99-per-month rate) and transfer your account to the web — something that can only be done once your current subscription lapses. "Pardon us if you can't do this immediately. Your current plan needs to end first," Spotify says.

Apple has received plenty of criticism from rival music services over the 30 percent cut it takes from in-app subscriptions. And those complaints have only grown louder with the launch of Apple Music, the company's own all-you-can-eat music product. Implementing pricing parity across the web and iOS would mean less money for Spotify, a company that already posts bigger and bigger losses the larger it grows. Apple is reportedly facing inquiries from the US Justice Department and FTC over its rumored pressuring of record labels to dismantle Spotify's free streaming tier, a feature that sets it apart from Apple Music.

Streaming music: Is there actually