IPHONE Gestures

after using Iphone i feel it is much more complicated and even after its compact size we need to engage both of our hand to operate.

Example if someone use their right hand to operate the phone so that person need to engage its left hand to swipe back, i mean what is the harm in giving an option to swipe from right as well as left both side, (will it cause any security issue) also the swipe from left do not work in all applications, in few apps you are forced to go back form the top left corner, i mean why so much of pain.

can someone have solution or new IOS will bring this freedom.