Credit Card acceptance on React-Native apps, with inventory updating

Hi,

I am building an iOS and Android app through React-Native for a brewery that wants to accept payment through it's mobile app.  The brewery is currently using Vantiv for card-processing, but I'm not sure how to implement credit card processing (not Apple or Android Pay) through the mobile app. 

Also, the brewery would like to integrate something that updates inventory when sales are made.  So, any help in that direction would also be welcome.

Thanks,

Ben