It was announced shortly after Stan Lee's death, at age 95, that he had recorded a cameo for the film and that it would be his final voice-acting role. Lord and Miller felt it was important that Lee was given a bigger moment compared to previous Marvel films because he was "so integral to the spirit of this movie," and considered his role "extra meaningful" following his death.
At the beginning of the film, the famous phrase "With great power comes great responsibility" is actually said by Cliff Robertson, who played Uncle Ben in the original "Spider-Man" trilogy with Tobey Maguire. The quote was pulled from "Spider-Man" archival footage, as Robertson passed away in 2011.
This film was dedicated in memory of Spider-Man co-creator Steve Ditko, who died on July 6, 2018, while this film was finishing production. However, this was not the only dedication, as a month before the film released, Stan Lee died on November 12, 2018; the film was dedicated to both of Spider-Man's creators.
When Miles first visits Uncle Aaron's apartment, the television is playing the television show Community (2009) (Season 2, Episode 1 "Anthropology 101"). The beginning of that episode shows Donald Glover's character Troy getting out of bed wearing Spider-Man pajamas. This was a reference to an unsuccessful 2010 online campaign to get Donald Glover a chance to audition for the lead role in The Amazing Spider-Man (2012). Miles Morales co-creator Brian Michael Bendis describes that image of Glover in the Spider-Man pajamas as one of the major inspirations for the creation of the character and the character's design. Additionally, Glover appeared as another version of Aaron Davis in Spider-Man: Homecoming (2017), in which he makes brief reference to his nephew. Glover also voiced Miles Morales in Disney's "Ultimate Spider-Man" cartoon series.
There are many small details in Miles' universe that set it apart from ours, such as using "PDNY" in place of "NYPD," and instead of Chance the Rapper wearing a "3" hat, he has a "4" on it (evident from a poster in Miles' room).
According to John Mulaney, the producers encouraged him to "have fun" with his role as Spider-Ham, so he added cuss words to his dialogue. He eventually asked what the rating of the film was; which was PG.
When Miles is scrolling through the contacts on his phone, the name "B Bendis" appears. This is a reference to Brian Michael Bendis, long-time author of the "Ultimate Spider-Man" series and one of Miles' creators.
One of the billboards in Time Square is for a film called Clone College, which is a reference to Phil Lord and Christopher Miller's canceled series Clone High (2002), which must have been more popular in this universe.
A restaurant named Romita Ramen can be briefly seen. This is a reference to longtime "Spider-Man" artists John Romita Sr. and John Romita Jr., who created "The Prowler" while still a teenager, his first professional work in comics.
When Jefferson is scrolling through his phone contacts, "S. Ditko" is shown as one of the contacts. This is a reference to Steve Ditko, one of the original creators of "Spider-Man" and one of the two men the film is dedicated to.
In the background of the scene in Times Square, there's a billboard advertising "Hi, Hello," an alternate universe version of "Oh, Hello," featuring Nick Kroll and John Mulaney. John Mulaney is the voice of Spider-Ham. Kroll and Mulaney also voice the two lead characters on Netflix's Big Mouth (2017), a show they both produce as well.
The first Spider-Man related movie to feature Gwen Stacy as her super heroine ego, Spider-Woman (Spider-Gwen). While Gwen Stacy did previously appear in the movies Spider-Man 3 (2007), The Amazing Spider-Man (2012), & The Amazing Spider-Man 2 (2014), she however never gained spider powers or became Spider-Woman in any of the live action movies.
When Miles is scrolling through his phone, the name "Sara Pichelli" appears. Pichelli is one of the artists who had worked on the "Ultimate Spider-Man" comics with Brian Michael Bendis, creator of Miles Morales.
Danny Dimian, an Imageworks veteran in charge of the visual effects of Spider-Man: Into the Spider-Verse (2018), saw the film's creative journey as a natural evolution of what the studio had been able to achieve over the last twenty years.
In the "Meet Spider-Gwen" movie clip, Gwen says she is "the one and only Spider-Gwen". When her origin is told in the movie itself, she says she is "the one and only Spider-Woman". In the comic book universe, Spider-Gwen is just her solo series' title (therefore, that code-name is used only for marketing purposes) while Gwen uses "Spider-Woman" as her in-universe hero name.
Spider-Man: Into the Spider-Verse (2018) marked Spider-Man's debut theatrical animated feature, both from Marvel Entertainment and Sony Pictures Animation. However, Big Hero 6 (2014) was released in 2014, sans Marvel Entertainment's involvement with the project; that film was exclusively a Walt Disney Pictures production in spite of the original property being a Marvel I.P. (intellectual property).
Unlike Over the Hedge (2006), Big Hero 6 (2014) and The Peanuts Movie (2015), which were also based off of comic strips, this movie also borrowed elements from the live-action films. The previous three movies were straight-up adaptations of the comics without any live-action films beforehand.
The trivia items below may give away important plot points.
Amongst all of the alternate Spider-Man suits in the deceased Spider-Man's underground lair are the Iron Spider suit from the "Civil War" comic arc and the suit from the Sony's PlayStation 4 game with the white spider detail.
There are several visual recreations of scenes from the various live action adaptions of Spider-Man. These include the famous upside down kiss from Spider-Man (2002), the train stopping sequence from Spider-Man 2 (2004), Peter Parker's infamous finger guns strut scene from Spider-Man 3 (2007) and an altered version of the ferry splitting sequence from Spider-Man: Homecoming (2017).
The Peter Parker of Miles' universe being blonde is a reference to Ben Reilly, the Scarlet Spider and a clone of Peter Parker, who for a time took over as Spider-Man and even dyed his hair blonde during his time as Spider-Man.
Though brief in his appearance in the post credits scene with Spider-Man 2099 and the 1967 Spider-Man, this film marks the first appearance of J. Jonah Jameson in a Spider-Man film since Spider-Man 3 (2007).