A priori, a wallpaper should not be something that affects the battery consumption of our mobile, but it is more related than we could imagine, although we are talking about specific cases on certain mobiles.
What is true?
Well, the truth is that it is something that can influence the battery consumption of our phone, and therefore its autonomy. But we are talking about some effects that can be noticed especially in a certain type of phones. We are talking about all those who have a AMOLED and OLED display. And it is that these screens can help reduce energy consumption compared to an LCD in the same environments. That is at least what we have been able to verify throughout these years. And it is that screen technology is key when it comes to increasing screen autonomy.
As you know, this type of screens turns pixels on and off independently to be able to display the images and characters in it. And most importantly, to represent the black color the pixels are kept off, in the same way as if we reduce the brightness. This is the same principle by which a dark theme can reduce the battery consumption of our mobile, because by showing darker colors, and therefore fewer pixels lit, or at least with less intensity, this energy consumption is very limiting. And if we talk about a wallpaper, the same thing happens. The blacker it is, the less consumption we will make of the battery, and therefore it will contribute to increasing autonomy. Even if we put a completely black wallpaper, we should notice a lower consumption.
Is it worth it to save battery?
Well, this has been a recurring theme for years, if it is something that helps reduce energy consumption. Well, it has been proven that this is the case, but the question should not be that, but rather how much the autonomy of the phone really lengthens.
Well, if we think that the time we spend in front of the home screen of our phone, where the wallpaper is displayed, is quite reduced, we cannot expect miracles in this regard. And it is that when we use this type of funds, it is useless to be using games, apps or browsing with white and colorful backgrounds, because the reduction in consumption will not be noticed practically at all. Therefore we can say that yes, battery consumption is reduced, but only in very specific cases, for example in emergency situations when there is almost no battery left.
What if my mobile has an LCD screen?
Forget completely about any reduction in battery consumption for this reason. Since to your phone, if it has this type of screen, it will not be the same to show a black background than a fuchsia or white one.
Since to display a single pixel of color, you will have to turn on the screen completely, so the energy savings are zero.