Who is the Indiana Jones movie based on?
The characters and stories are based in the story The Adventures of Indiana Smith, written by George Lucas back in 1973. It wasn't until he met up with Steven Spielberg in 1977 that the character (and name, changing to "Indiana Jones") took shape.
Is there going to be another Indiana Jones movie after Indiana Jones and the Kingdom of the Crystal Skull?
Yes, a fifth Indiana Jones movie is planned. The fourth movie, Indiana Jones and the Kingdom of the Crystal Skull grossed about $800 million. Harrison Ford and Shia LeBeouf are expected to return. George Lucas and Steven Speilberg are said to be completing the script. At the end of The Crystal Skull, it showed Indy's hat blowing to Mutt, symbolizing that Mutt was ready to become the next Indiana Jones.