The word “app” is an abbreviation for the term “application”, or, in the more narrow sense, “mobile application”. Apps are a type of application software which perform a specific function and can be downloaded onto a smartphone or other mobile device, for example a tablet PC. An app is not necessary for the functioning of the mobile device itself. However, it extends the functionality of the device. Apps enable the mobile device to, for example, record health parameters such as heartbeat, pulse, sleep patterns and give the user of the mobile device advice on a healthy lifestyle or feedback on processed data.