I'm typing this on my old iPhone 7 Plus. I had a new battery installed in July. However, starting at 100 percent charged, while it is turned on, the battery percentage visibility drops a percent or two every 5 minutes. I've uninstalled all browsers so the drain is not coming from open tabs.
ALSO, the top fourth of the back of the iPhone (starting beneath the flash/lens) heats up as the draining continues. Should I try getting a different new battery, or is the heating up a sign of a meltdown coming?