If you use Yahoo Mail to conduct your business email communications, use the built-in SpamGuard utility -- Yahoo's spam blocker -- and email filter options to secure your email.

Check your spam folder. Yahoo's automatic bulk-mail filter does a decent job of making sure unwanted emails don't get to your inbox, but it makes mistakes occasionally.

Yahoo, on the other hand, has rolled the feature into the latest release of its Android app, version 2.6. Now users can create, update, and erase filters without having to fire up a web browser.