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For added support the screen will rotate between the set orientation and its 180 degree counterpart before logging in. Once the login button is pressed the screen will lock to the orientation at that point. This was mostly implemented for Landscape mode where the users would wear the device on the arm, and they could individually select whether to wear it on the right or the left arm without having to change configuration.
LatelyIn v. 1.7.0.5, functionality has been was added to lock the device to a certain orientation all together.
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