Mitchel Broussard, writing for MacRumors last week:
Instagram CEO Adam Mosseri took to the platform over the weekend
to answer a few user questions on his story, shared by The
Verge’s Chris Welch. Among the many things asked, the topic
of an official iPad app for Instagram was brought up, and Mosseri
explained why we haven’t seen one yet.
According to Mosseri, the company “would like to build an iPad
app” for Instagram, “But we only have so many people, and lots to
do, and it hasn’t bubbled up as the next best thing to do yet.”
I don’t buy this for a second. Instagram isn’t some scrappy little startup — they’re a hugely popular, hugely profitable division of Facebook. If they wanted an iPad version of their app, they’d have one. They obviously don’t want one, and don’t want to explain why.
My best guess is they think engagement on the phone is worth more, so they do everything they can to drive you to the phone app. But that’s just a guess.