Bad puzzles I've hand-crafted about 50 Mashu (masyu, pearls, necklace) puzzles that are published in my puzzle books "My Puzzle Fix" 1 & 2, so I am very familiar with the pitfalls of designing these puzzles. Some of the puzzles in this app definitely cannot be solved by logic alone and require trial-and-error guessing. Others clearly have multiple valid solutions. Both are inappropriate for any spatial logic puzzle. Also, simple navigation helps are needed, such as a "play another" button on competition of a puzzle.
Harder than it appears I think most reviewers aren't understanding the rules. It will show solved even if you complete it ignoring the rules associated with the different pearls. But there is only one correct answer. Game is thought intensive.
Very good! Excellent complement to Sudoku, Numbrix, and Words With Friends; however, it has a couple of quirks: If you accidentally complete the loop having made a mistake, it says that the puzzle is solved (albeit in the red color), and doesn't allow you to undo in that circumstance; Next, if you take a call in the middle of a game, it doesn't return to the same game.
Pretty and well implemented. Only one minor bugfix needed: allow breaking a full loop to try again in the event of an illegal solution.
Very pretty graphics. But the medium level is a little difficult to use and the hard level impossible. Also, levels don't have unique solutions.
Pretty fun game. The only real problem is that you can win without the line being green.