Build a website that can extract MSISDN of user in Vietnam

I want to build a website that can get user's MSISDN if they access the website via smartphone (all platform). From what I researched it's possible to do it. Once you bid, you must provide me a sample website, I will access it with all of my smartphones, which come to a total of 4. Give me back the 4 correct MSISDN to pass the test and get started with the job.