The ringtone on Lloyd's phone is the theme song of Ninjago: Masters of Spinjitzu (2011), on which this movie is based.
The plot diverged from the television series. However, according to show Producers Kevin Hageman and Dan Hageman in a Tweet, the show designs will have some changes to match movie designs.
This movie was first hinted at in a bonus feature on The Lego Movie (2014) Blu-ray, called "Enter the Ninjago". In the short, an executive changes several scenes in The Lego Movie (2014) to feature Lloyd, because "kids love ninjas". Emmet suggests that instead of changing the movie to add a ninja, they just make a movie about ninjas, which the executive claims is a great idea. The rest of the short becomes a trailer for this untitled movie, which they claim would go on to be a major bomb at the box-office.
Lloyd asks if he can be the gold ninja instead of the green. This is a reference to the television show, in which he actually becomes the gold ninja.