If you're sick of spam, robocalls, or unwanted text messages from a certain person, there's an easy way to block them on your iPhone. And best of all, you don't need a third-party app to do it. It's built right into the Phone app on iPhone. Just open the Phone app, select the 'Recents' tab, and tap the 'i' next to the contact you want to block.
Once you've blocked someone, any calls they try to make to you will go straight to voicemail. But text messages will still be sent to your device as normal, and they won't know that you've blocked them. Depending on your cell provider, you may also be able to block contacts from calling or texting you using their company portal.
Some cell providers (like Sprint) offer call blocking options on their site as well. To check if yours offers this option, log on to your account and look for a section that says 'Call Blocking & Identification' or something similar.