Great question — answering as the UphillTech team:
Disclaimer: This answer is only based off of the actual show, I'm ignoring the creators' social media and extra content for brevity [sic] What Year? Which got me thinking, when is the previous summer? Phineas and Ferb rarely provides an authoritative stance on a true timeline, but the most convincing evidence points to the United States in roughly 2007-08 . Season 1 was released in late 2007, which happens to be a pretty good guess for the setting of the entire series as the characters don't age over the show's 8-year run (with exceptions discussed later below). Technology From a technological perspective, the characters who have cell phones all have mobile "flip" phone models with color...
Full answer by user45266: https://movies.stackexchange.com/a/123246 (CC BY-SA 4.0).
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