San Francisco, June 16 : Kobo, an ereader company which is a subsidiary of Japanese media and ecommerce group Rakuten, has asked for a probe into the Apple App Store for possible violation of competition rules in the European Union, according to a report in the Financial Times. As per the complaint, charging 30 per cent commission for e-books sold through the App Store was anti-competitive as the tech giant promoted its own product Apple Books, said the report on Monday, citing sources familiar with the complaint. The complaint was reportedly sent to the European Commission in March. A similar complaint was last year sent to the Commission by Swedish music streaming service Spotify. Spotify accused Apple of unfairly hindering its rivals and favouring Apple Music through its App Store policies. Rejecting Spotify's assertions, Apple had earlier argued that Spotify was really driven by "financial motivations" and wanted to benefit from the App Store's infrastructure without contributing to it. The European Commission has not yet ruled on Spotify's complaint, the Financial Times report said. These are not the only two complaints against the App Store in the EU. Tracking app maker Tile last month sent a letter to the commission, accusing Apple of anti-competitive behaviour. Apple "strenuously" denied the allegations. /IANS