Sometimes, your best bet is to stick with the basics, like a good old-fashioned prank call. Successfully pulling one off is another matter, though. That's where a new app from Ownage Pranks comes in.

A YouTube user who goes by the pseudonym Russell said ads for his 4.8-million-subscriber channel, "Ownage Pranks," have become more unreliable in recent months. When he tries to contact YouTube ...