A visual anti-alarm Android app.
It's a quick and dirty little app that aims to help with the situation where you tell a small child that some thing will happen or is allowed at such-and-such time (like waking up their parents, or watching TV), and they can't read a clock yet (or pretend to not know).
Set a target time and press "start", and you get an analog clock whose background starts out red (or whatever color you want), that also shows the target time as ghost hands. When the target time is reached, the ghost hands disappear, the background switches to green (or whatever color you chose). You can set a "we're getting close" duration and color, so that e.g. 5 minutes before the target time, the clock background turns e.g. yellow.
The clock activity is configured to keep the screen on and launch over the lock screen (so that switching the screen off and on again has the clock visible.)
You'll probably want to either pin the app after starting the clock, or keep your eyes on things until the keyguard kicks in under the clock, so that the children won't just press the home button and start watching internet videos.
Using the app is one-shot: Configure the clock to your liking, then start it. Press back (if not pinned) to exit the app, and launch it again for another run.
Needs Android 5.0 or younger to run (people tend to use old phones to give to their children).