When the app Store doesn't open, it could be a problem with the network. We can do this by clicking on the "Settings" app in the iphone interface, as shown in the following figure.
Then we find the "Wireless LAN" column in the interface under Open List settings, as shown in the following figure
Then we click on the "Info" icon in the incoming interface, as shown in the picture
Then in the wireless network details list, find the DNS column, delete the original address, the 114.114.114.114 fill up. When your phone's DNS address is set up, then open the phone backstage and exit the App store from the background and see if you can use the App Store normally.
Here we can use 8.8.8.8 to set up DNS, then we restart the phone to see if it can be restarted oh.
If the above solution can not be solved, we could try to restore the factory settings to solve the iphone restore factory settings
1, first restore the network settings--Enter the "Settings"