Which came first, Amazon or Android?

Amazon came first, by 14 years. Jeff Bezos incorporated the company in Washington state.

Side by side

Amazon

Amazon was incorporated on 5 July 1994, originally as Cadabra, and the website opened in July 1995 selling only books. The 1994 incorporation date is used here because it is the company's own founding date; if you mean the shop, 1995 is the answer. Either way it predates Google by three or four years and eBay by about a year.

Android

Android as a company was founded in October 2003 — four years before the iPhone — originally to build an operating system for digital cameras. Google bought it in 2005 and the first Android phone shipped in October 2008, fifteen months after the iPhone went on sale. So Android is older than the iPhone as a project and younger as a product, which is why the question needs the distinction stated.