What is the Coinbase app for iOS?

Could you elaborate on the Coinbase app for iOS and its functionality? I'm curious to understand what it offers in terms of cryptocurrency services. Specifically, how does it facilitate buying, selling, and storing digital assets? Does it offer any advanced trading features or security measures? Furthermore, is the user experience intuitive and user-friendly, or does it require a steep learning curve? Lastly, what are some of the key benefits of using the Coinbase app compared to other cryptocurrency platforms?