Sudoku for rookies

The app generates sudoku puzzles of different difficulty levels for you to solve. This app is aimed at inexperienced people who want to get started in the art of deduction and solving of this entertaining game. It has clues (last candidate / last box) that will help you achieve it. But this app also shows you how to narrow down the candidates using other techniques widely spread on the Internet. This version of the app uses the following techniques:
"Candidate Line"
"Box/Line Reductions"
"Naked groups" (double couples, naked triplets, quartets, quintets...)
"Hidden groups" (hidden couples, triplets, foursomes,.....)
"X Wing"
"Skyscraper"
"2 strings kite"
"Empty rectangle"

Learn and practice these techniques, you will start as a rookie and you will master the art of Sudoku.

Note:
In future versions other techniques will be implemented..... Stay tuned!!!