There are now happily a number of good B&W Apps available. A few new releases have some moody/dark capabilities that are fun. I particularly enjoy seeing what others are doing with these tools.
I've been doing quite a lot of B&W iPhoneography lately. I use the App "Simply B&W" quite exclusively and for my money it's the best. It seems to surpass all others in tonality and also has the most "Untz" to steal a phrase from another App developer...mid contrast I think.
I haven't been doing much posting so here are a few.