Revealing mistake: When Danny is hacking Twitter through brute force, the code executed on screen is not at all a hacking tool, but simply prints jibberish - actually I googled some lines I could easily pick up without pausing, and they were from a past year finalist of the The International Obfuscated C Code Contest. Entirely harmless easter eggs, certainly not hacking or cracking material. (00:10:35)
Revealing mistake: As Felix recollects the time when he and Vanessa were dating, he mentions it happened in their freshman year. The Roxy tweet that broke them up is dated 12 Nov 2014. When they show Felix's report card, it says it's for the 2014-2015 year, so it would merely be a couple months before. (00:09:10 - 00:15:40)
Revealing mistake: When Felix talks breaking the fourth wall about the mysterious, vicious "Roxy", he shows her twitter page. The latest tweet is dated Mar 10. Since the school at that moment still has to issue the report cards for the first semester, it seems a little too far ahead in time. (00:08:40)