Social Media Addiction Reduction Technology Act or the SMART Act This bill requires social media companies to structure their platforms in a manner calculated to reduce the risks of internet addiction. The bill prohibits social media companies from using infinite scroll, auto refill, and autoplay functions and restricts them from giving users awards for higher levels of engagement. The bill further instructs social media companies to automatically limit users' time spent on their platforms across all devices to a default of 30 minutes per day and to implement regular stopping points designed to end scrolling after 3 minutes. Social media companies are also charged to conspicuously display a notification at least twice an hour showing users how much time they have spent on the platform that day.