Phizaal

No worries man!

I would suggest the following:

• You already follow the 20%-80% rule :) Perfecto!
• Review your Background Apps setting (I recommend disable all and only enable one's that are needed!)
• Review your battery usage in the settings to find out what is draining your battery as it doesn't seem normal imo. ' I just use Instagram for 15 minutes and it’s already down ~10%.'
• Use a slow charger when possible to reduce the temperature of the battery when charging!
• Keep your screen's brightness as low as possible will help but is a bit overkill. just don't use max brightness all the time lol

I know some of these are over the top but they will help over time!

Safe travels to your next destination :)

EDIT: Here's a short video which runs through settings which can help with prolonging an iPhone's battery life :)

Re-installing the app will clear it's cache

It might be the 'Animated Art' being stored in the cache imo. Could try disabling in the Music settings (at the bottom) if you'd like to test :)