In his junior year, he became the first Temple player to average a double-double since Ollie Johnson accomplished the feat in 1970–71.

[4] As a junior, he averaged 12 points and nine rebounds per game, and was named a Top 150 player in his class by Hoop Scoop.

[7] In his senior season, Allen posted per-game averages of 13 points, 9.6 rebounds, 3.2 assists, 3 blocks, and 2 steals.

[7] Under Allen, Pennsbury reached the second round of the PIAA playoffs before losing to Harrisburg High School.

[7] He worked at a day care facility to earn enough money to bring his date to the senior prom.

[5] On November 8, 2006, Allen committed to Temple, over Division I scholarship offers from Rutgers, Saint Joseph's, and La Salle.

[9] Along with Dayton signee Chris Wright, Allen was one of two ESPN 100 prospects in the class of 2008 to sign with an Atlantic 10 program.

[10] Sources: Coming into his freshman season, Allen was selected to the Preseason All-Atlantic 10 Rookie Team.

[7] On February 10, 2008, Allen's season-high 20 points led Temple to an 80–70 overtime victory over the UMass Minutemen.

[14] The Owls finished the season 21–13, and made the NCAA tournament for the first time since 2001, receiving a 12 seed by the selection committee.

[26] He was recognized as an All-Fourth District first-team selection by the National Association of Basketball Coaches making him eligible for the State Farm Division I All-America teams.

[20] After one workout with the Portland Trail Blazers, Allen was told to return to school to work on his offensive game.

[32] Prior to his senior campaign, he was on the preseason John R. Wooden Award and Naismith College Player of the Year watchlists.

[35] On December 6, Allen was named Atlantic 10 co-player of the week after recording back-to-back double-doubles against Central Michigan and Maryland, both Temple victories.

Allen snatched 12 boards to pass Temple radio analyst Johnny Baum's career 1,042 rebounds.

[39] Allen scored a career-high 24 points to top La Salle in the regular season finale, earning him Atlantic 10 Player of the Week recognition on March 6.

[40] Temple finished with a 26–8 record in Allen's senior season and earned a berth to the 2011 NCAA Division I men's basketball tournament.

[42] Allen was the recipient of the Robert V. Geasey Trophy honoring the Philadelphia Big Five Player of the Year.

[43] Behind Chris Gaston of Fordham, Allen finished second in conference in rebounding average with an 8.4 mark in league play,[44] and was fifth in the Atlantic 10 in blocks.

"[1] On April 1, 2011, Allen participated in the 2011 Reese's College All-Star Game held at the Reliant Center in Houston, Texas.

Allen became the 32nd Temple product to be drafted and the first since the New York Knicks selected Mardy Collins with the 29th pick in 2006.

[52] The contract included an opt-out clause when the NBA settled its lockout, set to expire on January 30, 2012.

[53] Allen joined former Richmond foes Kevin Anderson and Justin Harper on Strasbourg IG.

[54] He made his debut on October 7, scoring 10 points and pulling down four rebounds in a 77–74 victory over Cholet Basket.

[59] Allen made his NBA debut during the 76ers' 97–62 win over the Toronto Raptors on January 7, 2012, and grabbed two rebounds.

[60] He first saw significant playing time on the January 23 game against the Washington Wizards due to injuries to centers Spencer Hawes and Nikola Vucevic.

With the score tied and four minutes left, Andre Iguodala passed the ball to Allen, who hit a 22-foot jumper as the shot clock expired.

[64] He missed two days of training camp to attend to his girlfriend, who gave birth to his son Kai on October 4.

[5] On February 20, 2014, Allen and Evan Turner were traded to the Indiana Pacers in exchange for Danny Granger and a second-round draft pick.

[81] In June 2017, the Pacers declined the $3.5 million team option for Allen, which made him an unrestricted free agent.