In case of placement of the pictures in the Instagram taken from my device (Sony of the Xperia of ZL) they turn out very bad quality, namely 640х640 points. The same photos sent to the Instagram from devices of other vendors are published in standard, at the moment, quality of 1080х1080 points.
The pictures taken on other devices, but sent to the Instagram from my phone also strongly worsens and are published in the amount of 640х640 points.
Various change of settings, deleting data and reinstallation of the Instagram don't solve a problem.
(The text is translated automatically from Russian.)