Here ya go:
The next time you get a spam message or you just want to block a new enemy or annoying family member from texting you, text the words
block [insert number here]
. Within seconds, you'll get a SprintFreeMsg response from the 9999 number confirming that all text messages from the indicated number will be blocked. You can also text
spam [insert number here]
to have Sprint "investigate" the number.
Check out a fun infographic that teaches you how to increase storage, enhance security, improve battery life and clean your device.