Implicit authentication (IA) is a technique that allows the smart device to recognize its owner by being acquainted with his/her behaviors.
[3] In Implicit authentication (IA), user behaviors (raw) data are captured by various sensors embedded in the smart device, and stored in the database preparing for further processing.
After filtering out noise and selecting suitable features, the data will be sent to machine learning tool(s) which will train and return a fine-tuned model back to smart device.
The utilization of the bio-metrics for user authentication had been developed in the field such as: location-based access control,[7][8] notably keystroke dynamics and typing pattern.
The current IA approaches mainly focused on touch sensor, GPS and accelerometer, and the corresponding techniques were SVM, kNN, GMM and topic model.