Wal-Mart on Tuesday launched its long-awaited internet film service, offering films from all of Hollywood’s main studios in a move that could see the retailer challenge Apple’s iTunes platform for supremacy in digital downloading.

Unlike iTunes, the Wal-Mart service has the backing of Warner Bros, Walt Disney, Paramount, Sony, 20th Century Fox and Universal. More than 3,000 film titles are being made available, including recent releases such as The Devil Wears Prada and Superman Returns.