Android software recommendations?

It seems many are still in active development. Just like the Sengoku period!
Many software locked functions to paid version.
While there are many choices even for the simplest functions, some areas are lacking pro ware.
I've only tried some and not sure how good they are.
Just share and see your recommendations or comments.

Wifi File transfer (no need for plug or unplug):
Airdroid: free, simple to use, need browser for interface
ES File Explorer: free, it's a file manager but also transfer file via LAN and Shared folder
Guide: http://howto.cnet.com/8301-11310_39-57583739-285/

Map and GPS - an area I'm uncertain
Online: Google Map seems great
Offline: Sygic (1 week free trial)? OSMAND (free)?
Many apps limit the number of free maps.
Some apps offer additional articles from wiki while charging a fee for downloading.

Dictionary & Translator:
Online: it seems to be Google again
Offline: Only a few offline dictionaries. No offline translator (I need Eng-Jp, Eng-Cn) ?

Music player:
For Samsung I use the built in, for other tablet I have no idea.
Google Play? WinAMP? PowerAMP?
What functions are cool?

Nothing as flexible as foobar2000 where I can search and filter songs quickly with tags or paths or any text stored inside the meta.

Video: MX Player?


To be continued (updated)