The Unified Payments Interface (UPI) is really a game changer - a single payment interface which introduces operability between banks, simplicity, reduces transaction failure rates, friction and enables new, better consumer experiences.
Here's a super simplified explainer feat. Suresh & Ramesh. This one is a more detailed PDF, eww PDF.
I believe its launch will mark a groundbreaking shift in the Indian payment landscape. It will allow startups to compete, unchained from previous constraints and from the terrible stock apps of banks.