brand new iPhone XS seems to run out of juice quite quickly - when should I charge it? I've been using a company iPhone for quite some time now, and I found it to be much better than my Android personal phone, so I decided to buy a 256 Gb iPhone XS. I like it much better than my Samsung, except for the battery - even if it's brand new, it runs out of juice pretty quickly (it may also be that I'm so happy with my purchase, that I end up overusing it - the UX is much better :-) What's the recommended routine for an iPhone? Should I charge it as soon as battery gets down to 20%? Sooner? Later?
Apple has a guide on how to maximize the performance of your battery.

Here are some of the key points:


Avoid extreme temperatures
Remove certain cases during charging(may cause excessive heat)
Store the device half-charged when storing long-term without usage
You may also want to check battery settings for what apps are using your battery and maybe disable background app refresh/location services for those apps
Make sure your display brightness isn't too high and enable auto-brightness if you want


Additional tip(not included in article): Keeping your device between 20%-80% helps your battery last longer. The website says keeping your device up to date also helps, but in many cases updating older devices reduces battery life.(the one exception to this is iOS 12 which actually improved performance and battery life)