PostureScreen (or LeanScreen or SquatScreen) apps can be used on multiple devices for no additional charge. However, all devices need to be using the SAME Apple account. If so, you can use under a subscription unlimited and up to ten devices. However, if the devices...
To resolve this, simply do the following: If you attempt to take a photo and the screen is black, it means, barring the obvious that your device case is not covering the camera lens, that somewhere along the line when you installed the application you denied the...