Amazon is delivering a major software update to its Fire tablets.

The update is considered the first major update to Fire OS 5, a forked version of Android powering Amazon's tablets. It brings all-new features, including something called Blue Shade. It basically changes display colour and brightness so that the tablets are optimised for nighttime reading.

Amazon knows people like to sit up in bed reading at night, so this update should make it easier on your eyeballs to do so.

Apparently, accordingt to Amazon, studies have indicated the blue light coming from tablet displays can affect sleep patterns and suppress melatonin production at night. To fix that issue, Blue Shade will let you apply filters that limit blue light exposure, add warmer hues, and lower brightness to a desired level for reading at night. Blue Shade will roll out over the next two weeks.

Another new feature in the software update adds more parental controls, including an Activity Center, which will tell parents how often their kids play games, read, or watch videos. The update will also provide access to kids' browsing history and show which apps have been used.

On the kid-side of things, Amazon is giving them a browser that can be enabled via Amazon Fire for Kids (Amazon's parental control center). It will serve up more than 40,000 child-appropriate YouTube videos and websites that have been hand-picked by a team of experts.

The update is headed to the Fire HD 10, Fire HD 8, and Fire tablets. It should be available for all those device within two weeks.