Apple iOS 11 Public Beta is now live: How to install it

Since it was announced earlier this month, iOS 11 has attracted a lot of attention. As usual, it was released to developers straight away and reaches the rest of us in the autumn. But if you just can't wait, the iOS 11 public beta program has just gone live. So, should you upgrade, how do you do it and what are the downsides? The I.F.O. is fuelled by eight electric engines, which is able to push the flying object to an estimated top speed of about 120mph.