With regard to the rights to the photos, none of the presented applications can really convince: For almost all, you transfer the rights to the respective service through the publication. If you like the variety of filters in the foreground, you should try out the iOS app Tadaaa, where you can customize the number of effects also individually. If you want to publish the pictures in as many social networks as possible, EyeEm and Hipstamatic are recommended. EyeEm also offers many ways to discover new photos and photographers by browsing.