An app designed to let moviegoers know when there will be a proper lull so they can run to the potty says it will be ready to go when Marvel fans attend "Avengers: Endgame" -- which is reportedly going to run just over three hours long.

The creator of the RunPee App tells CNET that fans typically should look for a scene in Marvel films that appears to lead up to a big battle. Regardless, creator Dan Gardner reportedly said the app will have “pee times” that will be spoiler-free and ready by opening night for "Endgame."

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"We’ve all been there, enjoying a movie, when nature calls. It starts with a whisper, then becomes a shout. Before you know it, you’re not watching the movie so much as watching for a chance to make a mad dash to the restroom," the RunPee App website says on its homepage. "The RunPee app takes the guesswork out of this for you. We watch every wide release movie to find the best scenes you can use, if you need to run and pee."

Fans are still waiting to hear when tickets will start going on sale.

RunPee App
The RunPee App promises to tell you the best times to run to the bathroom during a movie.
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