I took a few minutes to explore the Ten Frame app and alas, that is all it really takes to have the full experience. The Ten Frame app is simply an empty Ten Frame that the user can fill at will.
If you are so inclined, you can even fill up the Ten Frame with as many dots as you like-who needs 10? How about 20? How about 2 dots piled into one box?
As a tool to teach children the concept of ten, I think the Ten Frame should only allow a user to place one dot in a square. I also would prefer if there was some sort of timing mechanism that would click in so that once a user placed say, 1 dot, the rest of the frame would then freeze up allowing the user to see the 1 dot in relation to 9 empty squares.
I also think that the user should only be able to enter dots in a particular order, or at least the dots will align themselves in a particular order. The order I would propose would be left to right, starting with the first row. On a related note, I think the Ten Frame should also be oriented with 2 rows of 5 versus 2 columns of 5.
In a more "advanced" version of the Ten Frame, a number sentence could also appear:
ex. 1+?=10 or 1+9=10
Or a question could be asked, "How many more dots to fill in the Ten Frame?"
At an introductory level, I think there should be some sort of "tutorial".
The user would be presented with a series of Ten Frames and accompanying questions.
#1: An empty Ten Frame+the question: How many dots do you see? Answer 0
#2: A Ten Frame with 1 dot +the question: How many dots do you see? Answer 1
until the user reaches the Ten Frame with 10 dots.
For the first time user, say, the K student, this orientation process will hopefully allow them to see and learn to "read" a Ten Frame automatically, so that it becomes the quick visual tool it is supposed to be.
In its current form, this Ten Frame app is empty.