When should you replace a phone battery?
If you are asking when should you replace a phone battery, the useful answer is a practical timing range plus the one source or warning sign that can change it. Maintenance timing works best when a practical interval is paired with the manual, condition, and warning signs.
Short answer
Replace a phone battery when battery health is poor, the phone shuts down unexpectedly, or it no longer lasts through normal use.
Detailed answer
Use the short answer as a starting point, then adjust for your location, condition, device, recipe, schedule, or official source. When accuracy matters, check the current primary source rather than an old screenshot or copied post.
Practical notes
Keep a reminder, compare conditions, and re-check the source when timing can change. For food, health-like, safety, and official schedule questions, choose caution over convenience.
What to watch out for
Do not keep using a swollen battery.
Related questions
This page is general information. Dates, platform rules, safety guidance, and official schedules can change.