Remember last month when news came out about that new Facebook feature that lets you search for a link to add to a conversation? That just launched on iPhone.

It’s called “Add a Link”. What it does is let you click on an icon from Facebook on your mobile device (just iPhone for now), type in keywords to search for a link from Facebook’s index, and then share the link of your choosing. The idea is that you won’t have to leave Facebook to go and copy a link and go back to the social network to paste it. If it’s already been shared on Facebook, you should be able to find it and share it right from there.

“We think this feature makes it much simpler to share web links with your friends on mobile, whether it’s an interesting news article, a funny video, or a favorite recipe,” says Facebook’s Tom Whitnah.

In a blog post, as well as the following video, Facebook tells the story about how the feature came to fruition from an idea and a hackathon.

Fascinating.

Apparently this will solve a problem a lot of people experience on a regular basis. Personally, when I share links it’s usually a page that I’m already on, as opposed to searching for a piece of content to share, but I guess there are times when it could come in handy.

As I said last month, for those lucky enough to appear in the top results for these searches on Facebook, it could improve referrals significantly. In other words, Facebook optimization will effectively double as a new kind of search engine optimization for sharing within Facebook. I suppose the race is on to rank on Facebook for coveted keywords.

The company is planning to add the feature to both Messenger and Android.