Amazon.com Inc. AMZN, +1.02% will spend more than $1 billion annually on 12 to 15 movies that initially play in theaters, according to a Bloomberg report Wednesday. The ambitious outlay, believed to be the most by an internet company on theater-first movies, comes as Amazon dukes it out with video-streaming rivals Walt Disney Co. DIS, +2.11% , Apple Inc. AAPL, +0.47% , and Netflix Inc. NFLX, +1.07% who are plowing billions of dollars a year to create movie and episodic content.