Have worked on quite a few apps that needed payment gateway integration, with my huge experience and iOS specialization, I can definitely do the integration for you.
Relevant Skills and Experience
Individual Freelancer and long time iOS specialist developer, have integrated payment gateways and webservices/RESTAPIs in several app projects.
Proposed Milestones
₹5555 INR - After integration of PayTM SDK
₹5000 INR - After integration of PayuMoney SDK
Just to confirm and make sure, you already have the iOS SDKs supplied by PayTM and PayuMoney ?