The development of cutting-edge connected mobile applications nowadays brings out several concerns: Should one develop only for one mobile platform or more,and which mobile platforms should be targeted(Android,iOS,Windows or all)? If developing a multiplatform solution,should independent native applications be developed or should a cross-platform framework be used? The dimensions of the before mentioned issues can further be cut by examining the following: Who will application users be? Is application being developed from the scratch or is it based on some previous work? This paper tackles these issues by describing the development of the multiplatform system named SCOLLAm [in]Form by using Xamarin cross-platform mobile development framework.The cross-platform development approach was chosen in order to reduce the problem of the application sustainability since its functionalities are expected to be frequently modified and extended during the 3-year design-based development period.Moreover,the paper discusses the guidelines for choosing a cross-platform development framework and lays out the accompanying development challenges.