These are just some suggestions from my own experience and from that of some others. I do realize that some or all of those might have disadvantages I have not foreseen or programming challenges not worth the utility.
(1)
The move-confirmation box covers the clock, which makes it hard to judge how much time is left giving players who use move-confirm even more of a time disadvantage than they already had. I am not sure, but I believe the previous smaller box in the app did not have this issue. There is enough space on the bottom of the board for the clock on one side and the move-confirm box on the other side.
(2)
When a puzzle is completed after a mistake is made (so it is still counted as a loss) the green checkmark still shows with the "Victory!" text, it should just show the "Puzzle complete." text as when you press the "Show the solution" button. If you failed the puzzle it is failed, it should not say "Victory!".
(3)
When a challenge is created, it should make the colour clear as well as the mode, variant, and time control. I have created some coloured challenges recently as part of a tournament on discord, but the box does not appear to reflect this fact.
(4)
As have been suggested before, the app needs lobby access, as well as ability to create and edit studies (I have used the browser for that, but some features like changing the main line require right-clicking). This however is not a minor change and probably requires significant development.
(5)
Some sort of confirmation for creating seeks, as from the main page. On a small screen it is very easy to tap when trying to drag or such, and to accidentally create a challenge (specially from the home page). This results in aborted games that annoy and waste the time of other users.
(6)
Move confirmation for puzzles. I do agree that there is a disadvantage to this, namely the fact that being able to even move one piece aids in visualization of the position, you should really be solving the puzzle without moving anything. However, it is very frustrating to accidentally lose rating points. At least the "Show the solution" button could have a confirmation.
(7)
A hotkey for move-confirm, this is for browser users, to make move confirm less of a time disadvantage. This can reduce the problem of mouseslips that often leads to bitter exchanges in the forums.
(1)
The move-confirmation box covers the clock, which makes it hard to judge how much time is left giving players who use move-confirm even more of a time disadvantage than they already had. I am not sure, but I believe the previous smaller box in the app did not have this issue. There is enough space on the bottom of the board for the clock on one side and the move-confirm box on the other side.
(2)
When a puzzle is completed after a mistake is made (so it is still counted as a loss) the green checkmark still shows with the "Victory!" text, it should just show the "Puzzle complete." text as when you press the "Show the solution" button. If you failed the puzzle it is failed, it should not say "Victory!".
(3)
When a challenge is created, it should make the colour clear as well as the mode, variant, and time control. I have created some coloured challenges recently as part of a tournament on discord, but the box does not appear to reflect this fact.
(4)
As have been suggested before, the app needs lobby access, as well as ability to create and edit studies (I have used the browser for that, but some features like changing the main line require right-clicking). This however is not a minor change and probably requires significant development.
(5)
Some sort of confirmation for creating seeks, as from the main page. On a small screen it is very easy to tap when trying to drag or such, and to accidentally create a challenge (specially from the home page). This results in aborted games that annoy and waste the time of other users.
(6)
Move confirmation for puzzles. I do agree that there is a disadvantage to this, namely the fact that being able to even move one piece aids in visualization of the position, you should really be solving the puzzle without moving anything. However, it is very frustrating to accidentally lose rating points. At least the "Show the solution" button could have a confirmation.
(7)
A hotkey for move-confirm, this is for browser users, to make move confirm less of a time disadvantage. This can reduce the problem of mouseslips that often leads to bitter exchanges in the forums.