Since the Oreo update, things have slowed down a lot. Mostly with the launcher. Pressing the apps button or swiping to see the apps list sometimes takes 2 full seconds for a response. I initially wiped the phone and setup things from scratch. That worked for the first day and then back to more of the same. Restarting alone does not help. Wiping the cache partition from the boot menu and then starting up gives about 8-10 hours of usefulness before the responsiveness again subsides. Samsung support offered no suggestions other than to have somebody look at it (walk in or mail in).