Issue Description
Screen does not register touches or lags.
Common Causes
App freeze
Screen protector issue
Software glitch
Step-by-Step Solution
Step 1: Force Restart
Use model-specific method
Step 2: Remove Screen Protector
Test screen without protector
Step 3: Update iOS
Install latest software update
Step 4: Reset All Settings
Settings → General → Reset → Reset All Settings
Explore Further
Hardware inspection if persistent
Prevention & Best Practices
Use certified accessories.