Every so often we hear stories of people losing their mobile phones, often with sensitive photos on them. Additionally, people may lend their phones to friends only to have those friends start going through their photos. For whatever reason, a lot of people store risqué pictures on their devices. Why they feel the need to do that is left for another discussion. This behavior has fueled a desire to protect photos on mobile devices. One popular option are photo vault applications. These applications claim to protect your photos, videos, etc….
QR codes  have become quite popular due to their fast readability and large storage capacity to send information. It is very easy to find QR codes anywhere these days with encoded information such as a URL, phone number, vCard information, etc. There exist tons of apps on smartphones that are able to read / scan QR codes. The table below shows some of the most common apps and libraries for the major mobile platforms – keep in mind that there are many more apps than listed here….