My iPhone only takes Black & White Photos?

Did you accidently set your filter to Mono (Black & White)?

Check the 3 circles right of the shutter button and see if they are red/green/blue. If they are, your current filter is black and white, if not you should be shooting in color. To fix it, tap the 3 circles and choose "None" in the list of filters.

You'll see three over lapping color circles in the left part of the screen. Touching that will bring up the option you want for a filter. I believe once you choose a particular filter, it'll stay there until you change it again. Even if you close the camera app and do a reboot.

However, even on pictures that you have taken already. You still can change the "filter" that was assigned to it. This can be done in either the camera app or the photo app. Just press Edit and those same three over lapping circles comes up.

KOT

Thank you for the hint.

A filter is just a property. Deactivated it you will be shown the original.

The filter colors are not rendered into a photos file, the photo's data keeps unchanged in the camera roll.

For example: you shot 100 photos of an important event. You take a look at the camera roll and see many photos in weird colors, because you accidentally activated a filter. You can simply select this photo, deactivate the filter and get back the original.

Did You mean this?

I have already taken several shots with a filter accidentally switched on. Is it possible to restore their natural colors?

Did you not read my reply to the OP back in October? I stated that you can change already taken photos to whatever you want by editing them.

KOT