In this particular case, they specifically say it is because they are waiting for certain Camera API changes. I suspect it is probably related to the need to g

In this particular case, they specifically say it is because they are waiting for certain Camera API changes. I suspect it is probably related to the need to gather gyroscope / accelerometer data that is keyed to the individual frames of the video. Instagram is certainly capable of putting out apps for both platforms simultaneously. I don't think they wouldn't fail on that without a good reason.