Twitter began testing Circle earlier this month with a limited group, and now it appears to be starting to roll out to more users. The feature works a lot like Instagram's Close Friends, in that it allows users to post tweets to a specific group of people rather than all of Twitter.
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It’s unclear how many people currently have access to Circle. It appears that more users are finally seeing the feature appear when they start composing a tweet, but some users are still reporting that they don’t have access yet . Twitter spokesperson Joseph Nunez told The Verge that it’s still in beta. “We’re still testing Twitter Circle with a group of people across iOS , Android , and the web globally,” Nunez said. “The feature isn’t rolling out to everyone yet , but we’re continuing to gather feedback.”
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To check if you have access to your Twitter Circle, update your Twitter app or head to Twitter in a web browser. When you start composing a tweet, you'll see a drop-down menu at the top that says Everyone. From here, you can select Twitter Circle to limit your tweet to a select audience, or you can tap Edit to add or remove people from your Circle. Twitter won't notify users if you add or remove.

You can add up to 150 people to your Circle, whether they follow you or not. People in your Circle will see a note attached to tweets (and vice versa), saying: “Only people in @[yourusername]’s Twitter Circle can see this tweet.” Tweeting to your Circle is almost like having a private account, except it makes certain tweets instead of restricting access to your entire profile .
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People in your Circle won't be able to retweet anything you post to them, but they can still download your tweets. It's also important to keep in mind that Twitter's Community Guidelines still apply even if you're sending your tweets to a smaller audience.
Source of information: theverge.com
