Phones need 'bed mode' to protect sleep

Or you could just put the phone/tablet/computer aside an hour or two before bedtime. It's probably not a popular solution, people get defensive when you suggest they put their phone away.

It seems to be worse with the modern f.lux mode than classic f.lux.

Actually a bed mode will make a substantial difference.

Looking at phones or laptops or whatever screens at nighttime suppresses melatonin, which leads to people not feeling sleepy when they should, which makes them much more likely to continue looking at their screen than if they became as tired as normal.

It’s certainly possible to stay up doing something without blue light (e.g. reading by candlelight or a dim incandescent flashlight), but blue light makes a huge difference, and actively fights people’s ability to exercise self control.

Working to change habits is all well and good, but instead of telling someone who habitually binges on candy and cookies to stop eating any snacks at all, period, it would be a more successful intervention to take the candy and cookies away and fill their refrigerator with carrot sticks.

If you allow your eyes to adapt, the yellowness really isn’t a big deal, unless you’re doing something color sensitive like making art. Just stop worrying about precisely what colors are on screen.

Even if you’re casually looking at photographs, watching a television show, or playing a game, your eyes can compensate pretty well for a significant reduction in the amount of blue light, and you can have a perfectly acceptable experience.

Note, you’ll also want to dim or turn off other lights at night. In particular white LEDs of CCT ≥4000K are terrible at night, both wrecking night vision and disrupting sleep rhythm.

If you’re in an otherwise dark room, you can turn your display brightness as low as it will go and turn f.lux to its orangest possible setting and still browse the web, answer emails, write code, etc. perfectly fine. At such an extreme setting you might not be able to effectively enjoy photographs or movies anymore, but maybe right before bed isn’t the best time to look at photographs anyway.

In my experience, using a screen colour app just encourages me to use my phone more not less. Even with these apps a phone will still emit a large amount of blue light and having the light source so close to my face I still notice it disrupts my sleep.

If you believe using your phone late at night is harmful to you at all then why continue to maintain a that behaviour? Wouldn't it be much more beneficial to your health to avoid screens altogether at night? I'm not saying that it is easy but I believe it's a good healthy goal to aim for just like getting exercise and eating well.

To your point about unhealthy eating habits I totally agree. I just don't see phone addiction normally talked about as often as diet and exercise which is why I wanted to mention it.