Why is my iPhone so slow

Question

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

Answer 1

Actually, except for the methods you just referred to, a hard restart of the iPhone is a good choice.
Or Turn off Unnecessary Features
1) Disable Reduce Transparency & Reduce Motion
2) Disable Automatic Download (iTunes & App store)
Or use the iOS system fix tools like TunesKit iOS System Recovery, which can fix it without data loss.
Or Reset All Settings on iPhone
Just go to "Settings" > "General" > "Reset" > "Reset All Settings".