3/15/22: Still loving the MOBI Calculator since devs screwed up this one last year! 11/16/21: Disabled this app. Found one by MOBI that has TWO customizable buttons, saves your history as you desire, no ads, clears entries & works like a Calculator should work! *12/14/21: I still don't understand how devs can screw up a stock android calculator app and think it's good business to not listen to customers' complaints.