Fortunately, there is. We'll explain the real reasons that your iPhone is so slow and share some useful solutions to fix your slow iPhone problems.
4 Solutions to Fix iPhone Is Running Slow
Solution 1. One-Click to Boost up iPhone Generally, iPhone running slow is resulting from iPhone clustering with junk files, or iPhone running out of space. Cleaning junk files thoroughly and releasing space hugely are the easiest ways to solve iPhone running slow problem even after updating to iOS 12. Try iPhone cleaner software like PanFone iOS Eraser to free up memory space. Solution 2. Turn off Background App Refresh Solution 3. Update iPhone to the Latest iOS Version Solution 4. Clear Your Browsing History
Actually, except for the methods you just referred to, a hard restart of the iPhone is a good choice. Or Turn off Unnecessary Features