There are lots of filters that you can add for free that make this easier to answer. I use kindle fire and a bluelight filter. This has way more to do on your eyes than the res. Here is the skinny on all the research. I use Twilight on my Kindle and F.lux on my pc and my tablet. I hope this helps, also there is an eye health app on android that you can get
Description
Protect your eyesight with your iPhone/iPad!
This is a quit nice app which can reduce your visual fatigue and protect your eyesight! When you feel visual fatigue or strain your eyes for a long time, just open it!Portect your eyesight with rotational eyeball!
Why does it work:
Myopia results from asthenopia, staring for a long time.
This application helps in restoring vision and relaxing your eyes.
How to use it:
1 Open this application. Exercise and relax your eyes by following the rotational balls for 10 minutes every 1 or 2 hours.
2 Close your eyes and recall the movement, rotate your eyeballs.
3 We provide you with tips of how to protect your eyesight.
Notes:
1 Please don't move your head with the ball, rotate your eyeballs only!
2 This application is for recreation and relaxation only. It can not be used as medical device! Call your doctor if you have problem in your eyesight!
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