This isnt a hand-waving excuse, eitherit turns out app development is quite complicated.

Even something as seemingly straightforward as a port would still require an awful lot of work.

Its way more complicated and involved than the average user might expect.

An app developer working on project mockups in an office setting.

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Well, no, not right.

And to keep all those users, Instagram needs to keep trying out new features and refining existing ones.

So even if Instagram could shuffle people around, it wouldnt necessarily know exactly how many it would need.

A development team working on an app, diagraming functionality on a whiteboard.

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And if it guessed wrong, that could make things even more challenging.

Its unfortunate, but at least it is possible touse the iPhone app on the iPadwhile we wait.

A design team meeting about an app design.

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