Systems and methods for interactive mobile fitting of hearing aids are provided. The method includes a mobile device receiving a reduced size fitting data set having a set of sampling points from a hearing aid. The method includes interpolating the reduced size fitting data set into a continuous fitting curve presented at a display of the mobile device with user interface objects that each correspond with one or more sampling points. The method includes receiving a user input manipulating a user interface object. The user input adjusts a value of sampling point(s) corresponding to the user interface object to generate an updated reduced size fitting data set that is communicated to the hearing aid. The method includes generating a substitute complete fitting data set based on the updated reduced size fitting data set for application to input audio to generate modified audio that is output from the hearing aid.