Night Mode Suggestion
Sent to Apple:
Summary of the proposed feature:
I suggest that you add a system Setting called "Night Mode." Night Mode would set the UI background from white to black or dark grey, and would set Dynamic Text to be white or a user-definable, easy-on-the-eyes color (perhaps "terminal green" or a pleasing off-white tone). Unlike "Invert Colors," Night Mode would not affect the color of tinted UIButtons, photos, webpages, app icons, etc., improving consistency across the interface.
There is already something like "Night Mode" in Maps app. Maps automatically sets to a dark color scheme based on the time of day. This obviously improves clarity at night, in deference to drivers who are depending on their night vision for safety reasons.
My suggestion is that we, the users and developers, should be able to have a night color scheme in all apps, not just Maps. Night Mode would be able to be set to automatically trigger based on ambient lighting, display brightness level, time of day, or to manually trigger based on a toggle. Developers should be able to make a "night" version of their app's UI that would automatically activate when system is set to night mode if their app is made to support that.
I would even go as far as to say that you should call this "Dynamic UI," to go along with Dynamic Text. Developers would be able to implement Dynamic UI elements into their apps so that when the user changes to Night Mode then all apps that support Dynamic UI would adapt automatically to this.
Summary of the current problem:
iOS 7 contains lots of white space. This is great during daylight hours, especially in direct sunlight, where it improves readability. However, lots of white space is NOT great at night or in a dark room, like a movie theater, concert, a car at night, bedroom, studio, etc. In these dark settings, lots of white pixels induce the opposite effect from what you intend. White will not lend the "calming" effect your HI guidelines suggest it ought to have.
Rather, a white screen disrupts night-vision, interferes with melatonin production in the brain, and increases eye strain. Numerous medical studies (I can provide links if you want) have shown that white screens can disrupt sleep cycles by stimulating the same optic cells that get stimulated by the blue wavelengths from the sun. One study even showed this had a negative impact on cognitive function. I find that even on minimum brightness, the white is still very annoying at night.
Inadequacy of Current Solutions:
The existing solutions to this are not adequate. Below I explain why reduction of display brightness, and invert colors, are both not adequate to resolve this problem, due to how they violate the iOS 7 HI guidelines.
Why Reducing Display Brightness is Inadequate:
If the user sets their device to the minimum brightness, in my experience even then, it's too bright if you're in a dark room. I often find that by having to lower my brightness to reduce eye strain from white areas, now my photos and other app content all appears too dark. This means that all the white in the interface actually competes with user content in dark settings, violating the HI guidelines of "clarity" and "deference."
Why Invert Colors is Inadequate:
Currently the only option to avoid the white background of iOS 7 is the "invert colors" control, but that also breaks iOS 7's "deference" HI guideline by affecting all app content, such as photos and web pages, not just the white background. It also affects the background image of the home screen and all the app icons, making the system feel unfamiliar. I would say that "invert colors" also makes the system less clear by changing how icons appear and making all the system colors backwards, breaking the "clarity" HI guideline also.
Therefore I suggest that you add the "Night Mode" feature, as described above. I think this would go a long way to quieting any criticism people may have of iOS. If it's too bright and white for them, they can go with the dark look. I think even those people who criticize the whiteness of it will find that in bright conditions, it's better that way, so having the option to set it to light or dark based on the environment and user comfort leve would be ideal. With such an option I think iOS 7 will be much better received by the public. Half the time or more, we're in the dark. Please don't blind us.