My 4s has been upgraded to iOS8. I backed up my phone on iTunes before. Can iOS7 be restored directly?

Hello, this is impossible. You used to back up data such as phone calls and SMS applications in iTunes. ITunes backup does not mean backing up the whole system. You need to understand this.

At present, system verification below ios8 has been turned off (including ios7). The version that has been closed by Apple will no longer support users to brush to this version. Can only be upgraded, not downgraded.

Apple's upgrade brushing rules are very clear, because ios needs to connect to Apple's server when brushing. Once the verification of this version is turned off, if you brush this version again, you will not be able to brush it in, and you will report an error.