What is the most useful/easiest file manager app or transfer app to copy files to my Galaxy watch?

[bwrite]

Looking for the most useful/easiest to use file manager or transfer app to copy files to my watch.

Looking for any recommendations.

Free preferred, but will pay, within reason, for a really good app.

[KnoxFather]

Hello bwrite, most of the apps that accomplish this are poorly made. The best 3rd party app I've found is called AnExplorer. If you have a Galaxy Watch, then I'd recommend using the Galaxy Wearable app. It's probably the better option.