Senators have grilled Apple and Google in Washington over “anti-competitive” behaviour related to their app stores.
Representatives from Tile, Spotify and Match also gave evidence, accusing the two tech firms of charging exorbitant fees and copying their ideas.
Both Apple and Google’s app stores charge fees of up to 30% for in-app purchases.
The two companies said the fees were justified to provide security for users.
The Senate Judiciary Committee’s antitrust panel focussed on claims that Apple’s App Store and Google’s Google Play are anti-competitive.
Senator Amy Klobuchar said that Apple’s App Store was a “literal monopoly”.
She said both stores “exclude or suppress apps that compete with their own products” and “charge excessive fees that affect competition in the app store economy”.
Google Play and the App Store are where the vast majority of apps worldwide are downloaded.
Developers claim that because of a lack of competition Apple and Google can charge extortionate rates.