Ask HN: Basic Image Editing on iOS?

I have googled and google-reddited and tried a bunch of apps and, surprisingly, have yet to find even one.

Does anyone know of a simple app which will let me edit existing images, especially censoring small parts of photos?

It would also be nice to have an app which lets me make drawings from scratch.

I would like a free one, some ads are ok, if they do not get in the way of functionality. (I am mostly fregan and avoid using currency and do not have any credit cards.)