Iphone 13 Pro battery keeps draining

Using my own phone, Here are some useful tips I use on days when I know I can't charge my phone:

• Using LTE instead of 5G
• Low Data Mode -Data uses more power than data, and limiting updates and more to Wifi can conserve power.
• If apps are using more battery than expected, reinstalling them can help.
• Turning off features not needed, such as Improve maps and routing, and many privacy settings.

1. Restoring the device every year helps remove bloatware and let me start fresh -Ensure to backup important data to PC or Mac using iTunes or backup phone to iCloud.
2. I find myself getting a battery replacement at least every 3 years on my daily driver, from apple, this is usually less than $100 assuming you're getting it done from an Apple authorised repair centre, unless you have Apple care then it'll be free assuming that your battery health is under 80% health.

Learn more ⇢ If the battery in your iPhone drains too quickly - Apple Support