Apple on Monday released the second iOS 15 and iPadOS 15 update, fixing some leftover bugs and a security issue. You can update your iPhone or iPad right now by going to Settings > General > Software Update and following the prompts.
The changelog for iOS 15.0.2 isn't very long, but it does include some fixes to what were surely frustrating issues. Here's the list that showed up on my iPhone 13 Pro Max:
The security update includes a fix for a memory corruption issue that allowed an application to execute arbitrary code with kernel privileges.
Even though I didn't experience any of the issues noted above, I'm installing the update on my iPhone and iPad Pro right now. That security fix alone sounds like it's worth it.