The US Department of Justice sued Apple on Thursday for illegally maintaining a monopoly for its iPhone by stifling competition and imposing exorbitant costs on consumers. The lawsuit, also brought by multiple US states, attacked the iPhone for raking in hundreds of billions of dollars by making it difficult for consumers to switch away to cheaper smartphones and devices. The long anticipated case against Apple sees the company founded by Steve Jobs in 1976 clash with Washington after largely escaping US government scrutiny for nearly a half century.