E-commerce giant Amazon (NASDAQ: AMZN) reported better-than-expected earnings and revenue for the first-quarter, driven by tweaks in its logistics operations, as well as growth in its advertising and cloud computing units, according to Amazon CEO Andy Jassy. "Delivery speed really matters to customers and we've continued to get faster while improving our safety performance" Jassy said during a call with analysts Tuesday. "Over the past year, we've talked about how our regionalization efforts have helped to lower our cost of service. We've continued to inspect our fulfillment network for additional opportunities and are working on several areas where we believe we can lower costs even further while also improving customer experience." Amazon's first-quarter revenue rose 13% year-over-year (y/y) to $143.3 billion, topping analyst expectations of $142.6 billion. The company reported adjusted earnings per share of $0.98 versus estimates of $0.83. Operating income increased to $13.2 billion in the quarter, compared with $2.7 billion in the same year-ago period. Net income in the quarter increased to $10.6 billion, compared with $0.3 billion last year. Amazon's first-quarter revenue from third-party sellers services, which includes ...