A group of researchers claimed that any user of the smartphone is lying or not, it can be accessed through an application (app).
source
They say that these apps will basically work on the basis of algorithms. Apps have been designed to make use of Android phones for the time being. The study was done by a group of researchers from Denmark's University of Copenhagen. They said the algorithm was created based on many behavior of phone users. For example, they said that when someone lied on the phone, he took longer time. The hand movements are also more prone to lying.
source
The app is currently being tested experimentally. Researchers say that when somebody is lying on the phone, different parts of the algorithm will have red color. And speaking the truth, green color will show.
One of the members of the research team, He said, 'This ability of the algorithm can be compared to polygraph (the conventional instrument). However, our apps still have some limitations and it will not be right to use it in a big way. "The apps have been successful on several experiments, researchers said.
Source: CNET