Facebook offered to back Epic Games in a legal fight against Apple by giving evidence against the iPhone maker, as the social network continued to rail against forthcoming iOS privacy updates.

In a blog, Facebook VP of ads and business products Dan Levy said it is “committed to providing relevant information” in an Epic Games lawsuit accusing Apple of anti-competitive practices, by providing details of the effects of App Store regulations on its own business along with “the broader implications of the unfair policies that Apple imposes on iOS developers”.

Levy said the move was one of several Facebook is pursuing to address its grievances with Apple’s policies, including a plan to restrict how apps track iOS users’ activity.

Facebook is concerned about the potential loss of advertising revenue, though Levy focused on the impact on small businesses in the blog, arguing it would be “much harder” for them to reach customers and so compete with larger rivals.

The executive accused Apple of seeking to boost its own bottom line: “the truth is, these moves are part of Apple’s strategy to expand their fees and services business”.

Apple previously argued the change was meant to give users more control over their privacy, and advertisers would find new ways to deliver effective marketing.