Activists and workers are planning a series of actions on the lucrative sales day for the e-commerce giant.
An Instant Pot pressure cooker, 23 and Me DNA tests and personal water filters were the most purchased items in the United States.
Amazon workers in Spain, Germany and Poland are staging strikes to protest working conditions and hours.
Amazon's Echo and Kindle products were the first to go on sale. Other sales begin Monday at 3 p.m. EDT.