Snapseed, which was developed by Nik's Software. The next one has to be Filterstorm, this is another must have. It allows for very intuitive editing of your images. For black and white I use onOne's app Perfect B&W. A great app but alas not available anymore for iPad or iPhone. You can still get it but only for the Mac computer. What a pity because this is a terrific app. I wont make this post too long, so tomorrow I will talk about some apps I use for some special effects. Two apps I highly recommend, especially if you are seriously interested in this branch of photography is AppAlchemy by Dan Marcolina and his app Mobile Masters Let me know what you think.Maybe I should start a new blog just on Mobile photography.