Step 6: Check With IT
If you use your phone for work, you might want to check in with your IT department, if you have one, to make sure that the iOS 9.0.2 update is cooperating with enterprise applications and networks.
Enterprise problems are extremely common and we always hear and see complaints about them in the days after an iOS release. iOS 9.0.2 probably won't be any different.
If you don't have an IT department, you might want to think about checking in with a knowledgeable co-worker that already has iOS 9.0.2. Pick their brain and ask about performance.