Issue Description
Battery percentage jumps suddenly or drains unpredictably.
Common Causes
Battery calibration issue
Aging battery
iOS bug
Step-by-Step Solution
Step 1: Restart iPhone
Refreshes battery reporting
Step 2: Calibrate Battery
Use phone until near 0%
Charge uninterrupted to 100%
Step 3: Check Battery Health
Settings → Battery → Battery Health
Step 4: Update iOS
Fixes battery reporting bugs
Explore Further
Battery replacement if health is low
Prevention & Best Practices
Avoid frequent partial charging cycles.