One program that should be available on any smart phone platform (droid, palm, iPhone) is a countdown timer. I have one on my Palm Centro called BigClock. This is a clock, alarm and timer with very large numbers. I can use these numbers as slate information as opposed to just timing information.
In the example below, I've set the timer for 42 days, 13 hours and 38 minutes. When I hold the phone up to the camera, it becomes "Scene 42, Shot 13, Take 38". Very handy.
The original BigClock is still available for download, as is the newer, user compiled Treo 600 / Centro version. Check the web for a countdown timer available for your phone.
Step 1: And Here's the Video Version...
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