The smartphone maker wants to be the next Ice Bucket Challenge by encouraging users to record themselves sucking water from one cup with a straw and then delivering it to another cup. The purpose, apparently, is to demonstrate the difference between UFS 2.1 and UFS 3.0 storage technology.
https://www.notebookcheck.net/OnePlus-has-the-weirdest-Twitter-challenge-right-now-involving-drinking-straws-and-suction.422885.0.html