When Steve stops Lisa on her way to her car, her Walkman is attached to her belt. When she turns away from Steve toward her car, the Walkman is in her hand. When he tells her he's tired of seeing her with the bulky thing and she turns around, it's back on her waistband. It moves back to her hand as they make their way back in.
In the first act, Steve Jobs talks about the issue of Time Magazine naming "The Computer" as Person of the Year, instead of him and the Macintosh. Despite the scene taking place on Jan 24th, 1984, that issue came out in December of 1982 and the Time's Person of the Year from 1983 was Ronald Reagan and Yuri Andropov.
Steve Jobs tells Joanna that Skylab was an unmanned satellite. In fact, it was NASA's first manned space-station.
During the rehearsal for the iMac unveiling, Jobs states that they're "going to the next generation of I/O, 12 megabyte USB". USB 1.1, the version of the USB standard used in the original iMac operates at a data rate of 12 megaBITS, not megabytes, a difference of a factor of 8.
Steve asks Woz about his Nixie watch when they are speaking backstage at the NeXT launch, which takes place in 1988.
While Steve Wozniak does own that watch, it wasn't made until around 2005.
Before the 1984 Mac launch, we see Mike Markkula begin the shareholders meeting with sales projection while Jobs and John Sculley talk backstage; this didn't happen in real life as John Sculley had presented shareholders with this information.
In the second act, Steve Jobs refers to Woz as "Rain Man." The NeXT computer was introduced on October 12, 1988, and the movie Rain Man was released on December 16, 1988. The term "rain man" did not come into common use until after the movie Rain Man became popular. The term "rainmaker" existed, referring to a person with the uncanny knack of making things happen.
John Sculley is seen in the business lounge of Cathay Pacific talking on the telephone in 1988, with the old logo and font very carefully added to the background wall and jet bridge. However, in a distance shot seconds later, a Cathay plane with the current 'brushwing' tail logo adopted in 1994 can be seen.
During the Mac launch in 1984, John Sculley tells Steve Jobs that Apple's board of directors sent him as "the Steve whisperer" to calm Jobs down. The slang term "whisperer," used to refer to someone with an affinity for communicating with something stubborn, did not enter popular usage until the release of the novel "The Horse Whisperer" in 1995, and the subsequent film adaptation which was released in 1998.
With the exception for the VW Beetle, all the cars in the parking lot scene between Steve and Lisa in 1998 are from at least five years later - especially the license plate of the Ford Explorer, which begins with a '5'.
The NeXT Computer was launched at the War Memorial Opera House in 1988. The movie shows a pristine, beautiful opera house with sparkling chandeliers and painted walls. In fact, the opera house was in poor repair in 1988 and it wouldn't be until after the Loma Pieta earthquake that the house was cleaned up and redecorated.
When Steve Jobs stretches forward with delight upon hearing of the iMac sales projections, the cameraman and camera are (twice) briefly visible in the lenses of his glasses.
Backstage before the Macintosh launch in 1984, Steve Wozniak excitedly tries to describe to Steve Jobs the size and energy of the crowd in the auditorium. He struggles to come up with a suitable comparison and Jobs eventually informs him that he can't wait for Woz to come up with a metaphor. As Wozniak had used the work "like" several times in his failed attempt, the comparison would have been a simile, which is a kind of metaphor.