1. A method of simulating end user interaction with a user interface of an application installed in a client terminal comprising: providing a sub application, to be executed by a processor of a client terminal, for: identifying a user interaction session during which an end user interacts with an application hosted by a client terminal via a user interface which is displayed by said application on a display of said client terminal; iteratively identifying when a change in a plurality of user interface presentation states occurs, by detecting when said application presents a new visual form of said user interface; upon each of said iterative identification, capturing respective said user interface presentation states following said change; tagging each of said plurality of user interface presentation states with a runtime presentation timing of a time of said capturing; documenting each of said captured and tagged plurality of user interface presentation states; iteratively documenting a plurality of user inputs inputted by said user during said user interaction session, said plurality of user inputs are documented with reference to display areas of said user interface at a respective of said plurality of user interface presentation states during said user interaction session, wherein said plurality of user inputs are tagged with a runtime timing indication, wherein said plurality of user inputs including at least one of a single touch, a gesture, a closing claw action and an opening claw action; wherein each of said plurality of user interface presentation states comprising a unique ID; uploading said change of said plurality of user interface presentation states, said unique ID, and said plurality of user inputs to a network connected central unit; at said central unit: synchronizing between said change of said plurality of user interface presentation states and said plurality of user inputs by determining a sequential order of said plurality of user interface presentation states and said plurality of user inputs according to said runtime presentation timing and said runtime timing indication; and generating a user frequency map for each usage simulation using said synchronized change of said plurality of user interface presentation states and said plurality of user inputs by forming a sequence of frames emulating a video recording; wherein said forming said sequence of frames is by using a plurality of pre-captured screenshots each representing a respective one of said plurality of user interface presentation states according to a match with said unique ID.