As the title suggests, I am taking still images in SD and HD modes. They are all identical, really no difference. Even the live streams are perfectly identical! Tested on both iOS and Android. The images are all saved as 1080p irrespective of whether I select HD or SD. The 360p does work fine in saving files as 360p.
Worth to mention that there is really no motion in the well-lit living room where I am testing this. These are really static shots and the ideal scenario for this cam! Needless to say, the images do not even seem to be of SD quality.