Big Harp is a 10 stack double Klondike variation as it is played in Germany. In contrast to double Klondike it has 10 cascades instead of nine. The game is also called “Die Pyramide” in some German Solitaire books.

You can change the rules wether to allow only Kings being dropped on empty cascades, but the default of accepting any card is a bit easier.

So you play red on black descending and build cascades ascending by suit on aces. Just the good old Klondike standard.

Hint: If cascades are getting very crowded you need to tap on the right spot, making a card pop out. If it is the wrong one, tap a bit higher or lower until you can catch the right card (I recently discovered ways to improve that, but it will take time until it can be released).

I have prepared an article about Big Harp in the english Wikipedia for people who like to play with real playing cards.

Good Luck!