Ek sought Friday to clarify the 7-year-old company's changed terms after some users declared that they would quit the popular streaming music app in protest.
The Swedish company, which counts 75 million users, caused a stir this week when it instituted the new policy that indicated it would be able to access user information, including photos, location, voice controls and contacts.
The responses were indicative of a data-collection age where online privacy is a touchy subject.
Markus Persson, the Swedish creator of Minecraft, tweeted that he had canceled his Spotify account.
"Hello," he wrote to the tech company's Twitter account. "As a consumer, I've always loved your service. You're the reason I stopped pirating music. Please consider not being evil."
He wasn't alone.
In the aftermath, Ek took to his company's blog in an attempt to calm users' nerves.
"Let me be crystal clear here: If you don't want to share this kind of information, you don't have to," he wrote in a post. "We will ask for your express permission before accessing any of this data – and we will only use it for specific purposes that will allow you to customize your Spotify experience."
"We understand people's concerns about their personal information and are 100 percent committed to protecting our users' privacy and ensuring that you have control over the information you share," the post said.
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