I need a Rails/ Shopify App Developer to create a simple Shopify App

Hello... I need Rails/ Shopify App Developer to create 1 simple Shopify App. App Function: App to help Shopify Merchants to enable ShareBuy function on their stores. This ShareBuy Function will enable Sticky Bar (Add-to-cart Bar) on their Shopify Product MobilePage. So users can buy the product together with friends with discounted price. The function of sticky bar: - It will consist 2 buttons: Buy Now Button with Normal Price & Buy Together Button with Discounted Price. - Users can unlocked the Discounted Price by share & invite their friends to buy the product together. The function is same with this page (need to open in browser inspect, because the page is mobile-only): [login to view URL] or [login to view URL] ----> Please look also at images attachment below to understand better the sticky bar function. With this app, Shopify Merchants can create sticky bar like that for their stores. NOTE: For bidding this project, please show Shopify Apps that you have created. Thank you, Alv