IOS Calculator \ iPhone Calculator\ Apple Calculator is simple design style. In the IOS7 before， it use of Quasi-Physical design , its prototype is ET66 Calculator of Braun Company in 1987, designed by the legendary artist Dieter Rams, very classic. This calculator is free & ad-free. There are many other excellent calculator in Android. Google calculator is also very perfect. The purpose of developing this calculator is only to enable users to experience the products of different system platforms. Or for the original IOS system users to provide transitional products.</br></br>