If you don't have Play Store, you can download Titanium Backup from here : https://bit.ly/2BOJEUE

Titanium Backup has been updated to v8.1.0

  • Added official support for Android Oreo.
  • [PRO] Added the ability to backup WPA/WPA2 protected Wi-Fi networks on Android Oreo.
  • Fixed “Mark as installed from Play Store” when restoring apps on Android Nougat and above.
  • Major translation updates.