Preserving smartphone battery life: Some say we should never let the battery drop below 20%. How factual is that?

[Kross]

There are so many myths around making the battery life of smartphones to last longer. One of those myths is that not allowing the phone to drain below 20%would make the battery last longer?

Is that factual? Or just another of the many talks on the issue?

 

[Min George]

I don't even know which one is true. For me, I let my battery drain to about 4% before I charge again.

 

[eLdavis]

Yes i have heard about this, smartphone battery often comes with charge circle. Letting your battery drain below 20% can reduce your life circle.