For those of you with Garmin watches, I've written an app that acts as a 40/25 play clock (and a 60 second timeout timer). It's not up on the store quite yet, but I'll post it if I get a few requests -- I've tested it on my FR235, so if you have a different model let me know and I'll make sure it works on those models first.
Also, if there are any extra features that aren't included, I'm open to ideas. I do want to keep it relatively simple, low memory/battery usage and no-frills. It's just a giant number showing the time remaining.
I'm plotting out one that will include a game clock as well, but that will be a bit more complex and needs a fundamental redesign.
Current features:
40 second play clock, vibrates at 25 seconds and then at 5-4-3-2-1-0.
25 second play clock, vibrates at 5-4-3-2-1-0.
60 second timeout, vibrates at 15 seconds.
At any time, hitting the appropriate button will reset the clock to 40/25/60. For example, if the 40 second clock is under 25 and you need to reset to 25, that's a single button push.