This Week in Celebrity Twitpics (PHOTOS)

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Parties, new tattoos and family time. This week, celebrities kept busy and shared what they’ve been up to with their followers on Twitter.

Justin Bieber scared his followers wearing a Halloween mask while Demi Lovato had a busy week starting with putting her hands in cement with fellow X Factor co-stars.

Celebuzz has a roundup of this week’s most popular celebrity Twitpics!

Who jetsetted to London and which famous sisters made an appearance on ‘Good Morning America’ this week?

Pink has been traveling around Europe this past week and shared some of her ventures with her Twitter followers. The singer recently posted a photo of her and her beautiful daughter Willow about to board a plane to London.

The Kardashian sisters are promoting their new fashion brand, Kardashian Kollection at Sears, and were seen on Good Morning America this week in New York City. Khloe Kardashian Odom tweeted a photo of the sisters on their way to the show. In other Kardashian Twitpics, Kim tweeted a cute photo of her and boyfriend Kanye West sharing a hug.

It was a big week for the X Factor judges as their show premiered this past Wednesday night. Judges Britney Spears and Simon Cowell made an appearance on Ellen and Spears tweeted a backstage photo from the show.

Lovato, another X Factor judge, is enjoying her new duties on the show. The star tweeted a photo of herself at a party for Fox network with fellow co-judge, L.A. Reid and New Girl actress Zooey Deschanel. Lovato also made her mark in Hollywood by putting her hands and feet in cement at Gauman’s Chinese Theater in Hollywood.

For more celebrity Twitpics, check out the gallery above!