iPhone Battery Problems: Advice, Please

[steveroberts]

I have an iPhone SE purchased new about four years ago.

Lately, the battery is intermittently giving me trouble. Sometimes won't charge, sometimes dropping a lot on the percentage meter in a short period of time.

I'm wondering if it's time for a new battery.

And, if so, is replacement something I can do myself?

Thanks for any advice on dealing with this issue.

SR