Cloud application security is a set of policies, governance, tools, and processes used to secure collaborative cloud environments and applications deployed to the cloud. As cloud native application development grows, it's becoming more important for security, development, and operations teams to share responsibility for cloud application security, with developers taking on additional AppSec responsibility through DevSecOps. Cloud application security issues include unauthorized access, exposed services due to misconfigurations, hijacking of user accounts, data leakage, and distributed denial of service attacks. Implementing effective security measures requires a comprehensive approach, integrating secure measures like identity access management, encryption, threat monitoring, data privacy & compliance, and automated security testing. These best practices can help organizations keep cloud native applications secure at speed and scale.