I find ES explorer to do pretty much anything I need. Wifi, samba, bluetooth, wifi direct. Also free in the market, and allows root access (su permitting)
Tips for a pleasant XDA:
Search before asking. Someone has likely already asked.
Spell your words completely, and use punctuation. It confuses people when you use "u" and "ur" and "dat", or when you wrongly use "there/their/they're/your/you're".
Be nice. Don't be rude, just move on to another post without leaving a comment. We are not 7 years old.
And PLEASE, do not ask for the "best" anything. We all have our preferences.