Also a web developer. I don't understand the reason you'd even need a common term to distinguish between the two. Wikipedia and Facebook are websites. Tons of websites have interactivity. It's a spectrum. Why can't we just say "website"?

Since we’re being pedantic about the use of these words, I think it’s very clear that I said the word “app” because part of casual use around the time that smartphones came into common use in reference to the mobile app.

Before then, most applications were referred to as “programs” and were generally understood to be run on full computers. While mobile phones had mobile applications, no one was on their Nokia talking about using the Snake “app” on their phone. The word “app” (not application) hadn’t entered common usage.

But if you had already told them you wanted to access something from a laptop and they tell you there is an "app" then you can normally safely assume that it's not a mobile app.

Dear Friend, that is the exact frustration with that conversation. I ask “is there a website” and they responded with “yes, there’s an app”. To remove any assumptions from the conversation, why not respond with “Yes, there’s a website”? It would be the same as if I contacted a shoe store and asked “Hey do you carry women’s sizes?” and the clerk responds with “Yeah, we have shoes.” My question isn’t about the existence of shoes, but specifically women’s shoes. My interaction with that customer service agent was frustrating because they refused to acknowledge that there’s a common difference between an “app” meaning mobile app and a website. To them “app” and “website” were the same thing, and I argue that they are not.

Have you somehow never interacted with technical support or customer service?

The moron I got at my isp the other day insisted that “internet” and “wifi” were the same thing.

You can in no way assume that because you said laptop, they are directing you to a web app.