According to rumors, the new iPhone 8 will come out with much less colors than the old ones. The iPhone 8 will come out in autumn.
A japanese Apple blog wrote, that there is until now only a black color known. So this could mean, that the new iPhone 8 will not come out with a white color. It’s also possible that it’ll come out ONLY in black.
If people would want to change their phone color then, they’ll have to buy phone cases with different colors.
This japanese blog also wrote about a limited number of phones. So they’ll will be sold out very fast.