Case Study I: MasterTheCall Project

The MasterTheCall project is an iOS app, whose objective was to provide an app for hunters to practice animal calls. Basically, the recording of a specific animal call is imitated by an expert (Master Caller), is played for the user and the user practices against it. The user recording is compared against the master call recording, and a score is given. The main challenge we  had was how to represent the sound (recording) generated by the Master Caller in a way the user can ‘see’ and practice with. Also it was a requirement that the app should work in areas where there is no Internet access as it is the case where hunting often takes place..

Technical Approach And Solution

The core app functionality of rendering the birds call and the user call recording into graphical representation was a big challenge. We used Webkit audiocontext to generate array comprising of average frequencies. Another challenge was comparing the shapes to understand how much the imitated call got closer to the original bird call. Most of the time was spent in fine-tuning the app to deliver accurate results. For that purpose, we used an advanced correlation algorithm for shape comparison.


MasterTheCall app has proved to be a successful app which could handle any kind of animal sounds. The hunters could download from a library (from iTunes Store) the recordings of ‘Master Callers’, and improve their skills by practicing against them.