(Image Credit: Guy D'Alema/ABC)

ABC News' Karen Leo and Sharde Miller report:

Onstage, Usher has the moves, and the voice to match. On Billboard charts, his latest studio album, "Looking 4 Myself," has been number one.

Offstage, however, Usher is in a public battle with ex-wife Tameka Foster for custody of their sons, Usher, 4, and Naviyd Ely, 3. Cameras rolled last month as emotions overwhelmed the singer during a court hearing.

Driving those emotions was what Usher, in an interview with ABC News' Robin Roberts, called his "steadfast belief that a father is important in a child's life. To have the time that I've had with them has made them the young men that they are. I want to raise them to be responsible future adults."

Asked what he wanted to impart to them, Usher said, "No one knows your child like you do. And it is taking the time to actively be there. It's a day in, day out process. I'm actively doing it every day that I possibly can, and being the father to them that my father was unable to be to me."

If his album's title suggests he is searching for his inner-self, one thing Usher has found is his passion for giving back. More than a decade ago, Usher created a nonprofit called the New Look Foundation. The organization recently held its third annual World Leadership Conference at Emory University in Atlanta.

"Music is what I love to do, but this is my heart's work," Usher, 33, told Roberts. "This is what truly makes a difference. … Everybody has that story of someone that was able to influence them to make a difference in their life."

In 2007, a troubled youth named James Harris joined the foundation and quickly became Usher's mentee. "Why it's so important for me to serve and why I have so much fun," Harris said, "is because I know what service did for me. And I know and recognize that I would not be where I am today without someone reaching back their hand to me."

Usher said, "This is what I'd love to be remembered for. Sure, having number-one albums, selling out concerts … but [also] being this type of mentor and being a positive influence to someone else."