The California-based company apologized over the issue on Dec. 28, cut battery replacement costs and said it will change its software to show users whether their phone battery is good. The letter also said they were concerned about reports that an iPhone battery overheated and began to emit smoke in Switzerland.
U.S. Senator John Thune, who chairs the Senate Commerce Committee, sent a similar letter to Apple on Tuesday. Apple did not immediately respond to a request for comment Friday.
(Reporting by David Shepardson; Editing by Chris Reese)