Some users with mobile seem to be unable to click on any button when they enter site

[Tianguistengo]

this happend for the first time in an iphone but it happened today again with tib kat in his android, I've asked him about version of browser and device, still waiting for response

[Tianguistengo]

it happened to him in the in-built browser of hangouts application in mobile (so I'm guessing chrome?) and then he tried firefox and it worked well there