Robocalls are at an all-time high. On average, Americans received more than 2,000 robocalls every second in October, up 25% from the previous month. With 49 billion robocalls so far this year, all four major U.S. phone carriers now offer some form of blocking or screening service, such as T-Mobile's well known "Scam Likely" label. Congress and state officials passed new robocall regulations in recent months and have seen an uptick in successful cases against the scammers. Meanwhile, hundreds of tech start-ups are developing new ways to tackle the problem.