Gmail is the best free Web-based email client for individuals, and not surprisingly, Google's Android app--optimized for tablets--is a winner too. Though it lacks some of the features you'd get using Gmail in a desktop browser, many of the most important functions are here. You can set your Priority Inbox to be your default inbox, manage multiple Gmail accounts, report spam, add labels to messages, mark messages as not important, and view and save attachments. Gmail makes great use of the tablet screen, with a list of messages in a left-hand panel and the selected message at right. You get all this and more--without ads.