Very well done, looks excellent...
I do have a couple comments though, if I may... You are able to change the orientation during game... This changes the grid from 6x9 to 9x6. Isn't that changing my options? Like if I can't move in Landscape, will changing it to Portrait give me alternative moves? I couldn't get my head around that lol...
Also, I notice that moves like 3 across and 3 down don't count. Take below for example, if I swap the 'A' tile with the 'B' tile (top left), I only get a match of 3 either on the horizontal row OR the vertical row, and not both...
BABB
DBCD
FBCF
I got 5 in a row at one point too, and that only registered as a match of 4
And lastly, if I try to exit game whilst the 'Congratulations' message is being displayed, there appears to be a 'depth' issue...
Using AppGameKit V2 Tier 1