Supported music formats by Samsung galaxy?

What music file types are supported by the gear s2 and Samsung Galaxy S8?

m4p?

m4a?

wma?

I have a bunch of music files acquired through the years in different formats, saved in iTunes library, and can't seem to get consistently to play by my phone's Samsung Music app. 

My goal is to be able to access these music files from my phone and also load some files onto my Gear S2.

Is there an app I can use to convert them into a format supported by the Samsung phones and GearS2?

Much appreciated