Limited iOS 9 Release
You can count on a limited iOS 9 release for iPhone, iPad and iPod touch. Don't expect Apple's update to land for everyone.
If you aren't currently running iOS 8, there's no chance that you're going to magically get bumped up to iOS 9. We're looking directly at iPhone 4 users and owners of the original iPad. You're going to remain on iOS 7 forever.
iPad 2 and iPhone 4s users should not count on an iOS 9 release. The iPad 2 defied the odds when it received iOS 8, its fourth update, and it would be shocking to see Apple offer a fifth update to iPad 2 users. (We hope it does.)
Apple tends to keep its iPhone models updated for three years before kicking them to the curb. iOS 8 represented the third iOS update for the iPhone 4s so the device is walking on thin ice.