[Help] How to make "Buy" button following scroll with the page (mobile native)

[bluifox]

hi guys,

 

i'm looking for tutorial how to make "buy" button following scroll while page scrolling. exaclty on mobile native.

 

this one is example : https://blazbluz.com/faybluz/suami_oktober

 

or

 

https://www.produkeksklusif.com/product/vintage-watch/

 

or what else this function is called ? sticky button ?

 

 

there are so many guide about how to make fixed top menu while scrolling page, but i didn't found for this one.

 

 

thanks for your help

Edited May 10, 2017 by bluifox (see edit history)