The plot i can remember is this: a girl goes to college. She’s very quiet. One day she gets invited to this guys house. While there, an app/website/video starts using a phone virus to make humans ‘zombies’ and the rest of the group decides to stay there. It grows something in the brain when you watch the app/website/video (which i think could grow out of the brain to show the infected as a zombie). Both she and the guy she likes get infected and get rid of the thing that grows inside .Everyone is picked off until she’s the last one alive. I remember her with an axe at the end, the world looking destroyed with the zombies going to get her.