Improvements to ShapeMatch?

I am considering making some improvements to ShapeMatch. Here are the things I have in mind:

• Changing the scoring system - I am not too sure I want to do this because the game targets toddlers, and I don't know the value of keeping score for kids that age.
• Adding sounds - Thinking about adding sounds to describe each shape. "Circle." "You matched the circle!" Of course, I would include a Settings menu item to disable the sounds.
• Adding different difficulty levels - Currently there is just one 4x4 grid. I don't want to go any bigger because the buttons are just the right size on my Droid for my kid's fingers. But I would consider smaller grids, maybe 2x2, 3x2, 4x2, 4x3 grids.
• Making the matched cards disappear or become disabled - the matched cards serve a UI purpose: you can touch an matched card to get an unsuccessful match to turn over. If I added this, I'd probably add the next improvement
• Adding a timer to turn cards over after an unsuccessful match - this would remove the need to touch a card to continue after an unsuccessful match, but it would consume extra battery life to run a timer, which is a side effect I don't like.
• Improving the graphics - I am not a designer, but I could play around in Inkscape some.

What improvements would you make to ShapeMatch?

Shape Match 1.01 released!

Shape Match v1.01 released to the Android Market today. It is a simple memory game that features 8 pairs of shapes that must be matched by exposing pairs.

Here's a screenshot:

Shape Match keeps "score" by recording the number of pairs that have been exposed.

It's a really simple game that is aimed at toddlers. I wrote a version for my personal use to keep my little girl entertained during a trip last December. My goal is to keep the app very simple; I found that it worked best for my own child to keep the shapes large and the interface very simple. It was also very important that the program maintain state when the screen switched from portrait to landscape and back and when the home button is inadvertently pushed. I hope it works well for you. I'd be happy to hear your feedback.