Among several diaries available for iOS, I found Narrato features very impressive. It allows every type of register, from location to text to pictures, has autosave features and shares the diaries among iOS devices and a blog. Its interface with Foursquare is a must. But it has two serious drawback: 1) pictures within the application are limited to a low resolution 0.7-megapixels (1024x765) images. Pictures imported from Camera Roll also have their size reduced to 0.7-megapixel even if you have a iPhone 5 capable of taking 8-megapixel pictures. 2) pictures exported or saved from the application to Camera Roll also have their georeference tags removed and can not be located anymore on a map!