Right now, the latest version of iOS is 9.1. Mine is 8.1.2. Can I use the restore option in iTunes to install version 9.0.2 or do I have to update to 9.1 and then downgrade to 9.0.2?
I just did this. Use ipsw.me to download your version (9.0.2). You can restore from any version that's green. Red means Apple isn't signing it. Press & hold option when clicking Restore in iTunes. Select the downloaded
Do note that time is of the essence. Once Apple stops signing the 9.0.2 firmware, you will be forced to upgrade to a current OS image.