User submitted puzzles is what makes this the best. – Puzzlium — The First Puzzle Social Network Review

You can choose to do different puzzle varieties and difficulties as well as create your own. I've never been too good at Sudoku but I found those the most fun. I'll have to try my hand at making one. It makes you sign in with Facebook, Twitter or google plus but that's not too bad. Overall it's a fun puzzle game that has a huge amount of user created content.
Review by Zak Sidhu on Puzzlium — The First Puzzle Social Network.