Twitter index: Ryan O’Shaughnessy, Cody Robert Simpson, Believe tour

Fans of pop singer Justin Bieber and of One Direction are expressing their excitement over Bieber's upcoming Believe tour and the end of the British-Irish boy band's Up All Night tour.

Bieber takes to the road on his Believe tour, which begins September 29, 2012, in Glendale, Arizona, and ends April 22, 2013, in Stockholm, Sweden. Tour dates and tickets were confirmed on July 2, sparking the trending topic "Believe Tour."

One Direction's Up All Night Tour ended on July 1 in Sunrise, Florida, after beginning last year on December 18. The end of the tour caused many Twitter users to reminisce over the tour or express regrets at having missed out on tickets.

Continuing the teen-pop theme, Twitter users are expressing their adoration of 15-year-old Australian artist Cody Robert Simpson and, using the hashtag "#AskRyan," posing questions to Ryan O'Shaughnessy, who came to fame after reaching the finals of the sixth season of British TV program Britain's Got Talent in 2012.

Microbloggers are also expressing thoughts about how they will treat their future offspring with #ToMyFutureKids and sharing their music tastes with "Now Playing."

The top 10 most talked about topics on Twitter on July 2 at 12:40 PM GMT are:

01. #ToMyFutureKids
02. #qanda
03. #AskRyan
04. Up All Night Tour
05. Cody Robert Simpson
06. Believe Tour
07. Now Playing
08. Aziz Yildirim
09. Sophie Mirabella
10. PREP