how to block bit.ly

I did some digging and this is a known spam text. These instructions I found online should work:

First, create a new contact called Spam Text or Unknown Person or something. For the phone number in that contact, enter 000-000-0000. Then scroll down and click "Block this caller". That should prevent texts/calls from numbers that aren't numbers!

You can also go into settings > Messages and turn on "Filter unknown senders" which will sort out all unknown texts into a different area.

Yes, I'm having this same issue -- very aggravating that someone can come through the iPhone without any email or phone number attachment to it -- all greyed out. I also went to Apps in iTunes and clicked on the only bit.ly tools I saw and when you click on the developer's website, it doesn't exist! Apple needs to look into this!