ClapperPod SP -Drawable Clapperboard- for iPhone 4+

Pretty good

This is actually surprisingly good, the ability to write on the screen being its main drawcard. No pun intended.

May I suggest some key updates to the developer to make it even better?

(1) have the sound of the clap override the mute button on the iPhone. That is, you can have your phone on silent and still use the clapper app, rather than what you have to do now, take the phone off silent, use the clap, put the phone back on silent before you continue filming. Putting the phone on and off silent detracts from the usability.
(2) although it's cute to have just the clap arm lift up and down, it's still small and there's no reason why the whole screen can't flash orange, for instance, for the one frame when it strikes. The editor should be able to use the whole screen to see the one frame strike instead of a microscope looking for the clap arm right up the top.
(3) good to have some tone chirps lead up to the clap, say three, that way when you're editing and you're looking for the waveform of the clap, on the audio file, you can see the three peaks leading up to the main clap. So when you activate the clap it should go chirp chirp chirp CLAP!

Make it so and it'll be 5 Stars!

Keep up the good work!