Selling your pictures you take via your smartphone is a option for smartphone owners. If you are a good photographer, you should consider joining the two sites featured in this post. PicaStock will be the earning app mentioned.
PicaStock
Similar to Foap and other apps that allow you to sell your photography from you cellphone, PicaStock consider themselves to the app to some of the best authentic photos and discover new ones. The earning app also allow you to share your photos on social media and see other photographers taking similar photos. If you have photo on your Instagram, flickr, or dropbox, you can upload them as well. In regards to pay, PicaStock rewards users with a 50% commission on each sale. There is more information about PicaStock in the PlayStore.
PhoFun
According to the app description, PhoFun is one of the newer apps in this space. After reading the app description, it seems like the have a point system. There was no conversion rates mentioned. The app seems to help there users, they give helpful information about titles, and even offer missions to earn more coins. For more information, use your cellphone and learn about the app yourself.