TouchCounts - In TouchCounts, children use their fingers, eyes and ears to learn to count, add and subtract. By using simple gestures to create and manipulate their own numbers, children develop a strong number sense. TouchCounts offers two experiences: The Numbers World and the Operations World.
Ten Frame Mania from Greg Tang - numbers roll through the track, and the player’s job is to show the leading number on the ten frame. Clear all the number before reaching the end of the track to progress to the next level. Very quickly, players can unlock the ability to fill 5 or 10 at a time. In other words, it’s quicker to make 4 by filling 5 and taking one off.
Euclidea App for iPad/iPhone - This free app allows students to solve geometric problems by using compass and straightedge constructions. I really like the way it allows students to explore constructions and builds up to more and more complicated constructions gradually.
These resources were brought to the attention of the MTA. The MTA does not officially endorse any resources listed above - this is for information purposes only.