This is THE BEST chess clock ... – Chess Clock Expert Review

... And I've tested them all. Goodbye to my expensive Chronos, this is better. And it's always with you. You can orient the clock in all ways, including while in landscape mode. You can add a LARGE number of stages to a custom time control. (There's a trick, though: The final stage is always automatically set to "Game," with no specified number of moves designated. So in order to set the number of moves in an added stage, you first must add another final "Game" stage, then go back and set the number of moves in the previous stage. PLEASE DELETE MY PREVIOUS REVIEW WRITTEN BEFORE I LEARNED THIS TRICK.) Each stage can have its own number of moves and Delay type. Both stage number and move number appear on the clock face while running. You can pause and edit both time and moves during the game in case of some error. Works smoothly. But Pedeclaudo is correct: This app doesn't recognize your upgrade purchase when you try to set a custom hourglass stage -- needs fixing. "Six stars" if the developer adds the ability to edit the listed ORDER of saved custom time controls. "Seven stars" if he adds the ability to make a time stage repeat seemingly ad infinitum, such as "20 moves in each hour thereafter." (Currently, programming the latter requires piling up a large number of repeated stages, just to be safe.)
Review by Nimbleswitch on Chess Clock Expert.