I've been kind of shocked with how poor the battery is on the 15. Granted, I went from a 12 mini to a 14 plus to a 15. I hated the size of the 14 plus, but loved the battery life and that it was the 2nd lightest phone last year. This year I opted for a more traditional size. Forget the indexing argument, I've had it for 5 days now. It's been off the charger for an hour, hasn't handled a call, screen hasn't been on, and I just checked and I'm at 88%. The other day I was tracking a football score and I lost 50% during the first quarter. In a year with the plus, I think I only ran it below 25% maybe 2 times. I've been getting below 10% with the 15 each day regardless of how I use it. Generally I track baseball/football scores, text, light emails, and call....that's my main usage.