Finally, I will explain about efficiency. iOS is safer than Android because Android can connect aircard outside, while iOS cannot be connected aircard because the design to strengthen security and also the speed iOS to prevail over Android. The iOS is a closed system. It is designed so that people know that only Apple devices, circuits and hence the speed of iOS devices are more and more stable as well. However, Android is altered by other equipment which makes overall instability and for this reason, cause there iOS security and stable than Android.