If you upgraded to iOS 10 but didn’t like it and want to downgrade, tough luck, because Apple today closed the door on downgrading from iOS 10. The company is no longer signing iOS 9.3.5 which basically means that it’s no longer allowing users on iOS 10 to downgrade to iOS 9. It has even stopped signing iOS 10.0.1 so it’s now impossible to revert back to that particular version as well.
Naturally, Apple wants its users to always be on the latest version of its operating software but it’s not like all users have the optimum experience. This is particularly true in the case of those who own older devices. They are likely going to experience some compatibility issues with iOS 10 and would want to revert back to iOS 9.
It’s not uncommon to hear about users with old devices facing issues on newer versions of iOS, while many say that iOS 10 is better on older devices than some of its predecessors, the fact remains that those who want to downgrade can no longer do so.
There might be tricks and other unsupported workarounds that claim to make that happen, but it’s unlikely that any of them are going to work now that Apple is no longer signing iOS 9 on its servers. The only remedy for those who are facing issues on their older devices is to buy a new one.