5 stars: This is the best way to study chess books. As you play through the lines in games/ problems, the program can instantly return you to the point in the game where the line began. (I can almost never remember where the pieces were at the start of a line, which was very aggravating and time consuming. ) The only shortcoming here is that not all chess books are available in this format.
4 stars: Very handy app for reading chess books on the daily train commute to work.
4 stars: everything is excellent, but if I rotate my phone, the text goes back to the beginning of the chapter, which can be annoying at times
3 stars: Idea is good! Need to upgrade and improvise. Can't differentiate between White and Black pieces.
3 stars: I can get the app on my Windows 7 computer, but it doesn't work on my Android 4.1.3 tablet...it doesn't even install!
2 stars: After latest update cannot purchase any new books. Using Samsung S10+
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