Three things in life are certain: Death, taxes and e-mail spam. Here's how to take care of it in Android's gmail app.
If you open an individual e-mail and then realize it's spam, hit the menu button. Depending on what phone you have, you mmight see the "Report spam" button there. It varies. If you don't see it, hit the "More" button. Then you should see "Report spam."
If you're in the inbox, you can select multiple e-mails, then hit menu, and you sould see the "Report spam" button.
Die, spam, die.
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