Fire OS 5.3.1 Release Notes
Your tablet has been updated to Fire OS 5.3.1, a free software update from Amazon that adds a number of new and exciting features. We hope you love these features as much as we’ve loved building them!

Encryption – You can encrypt your accounts, settings, downloaded apps and their data, media, and other files on your Fire tablet.
Blue Shade Automatic Activation – If you want Blue Shade to gradually turn on in the evening and gradually off at sunrise, you can turn on Automatic Activation in your Blue Shade settings.
On Deck – On Deck is now available on 4th Generation Fire tablets in addition to 5th Generation Fire tablets. On Deck downloads Amazon Videos to your Fire tablet so you have something to watch even when you are offline.
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