Only one time use.
Think of like world leaders, celebrities, ya know 😉. Are you gonna make them do some embarassing things, or illegal acts.
My answer:
spoiler
Take control of an NSA agent with access to the most powerful hacking tools, hack everyone’s phone, install a program that randomly have a popup at random intervals, the popup message says “I’m watching you”. This also tries to spread itself to any other phone it can connect to. Pure chaos 😈
Pretty sure I can do this in a minute, depending on how good the NSA tools are.
The person who approves or denies new shows on Netflix or something and then spend the next minute approving as many animated shows as I can.