A system described herein may allow for the masking of user input and/or sensor data, which could otherwise be used to uniquely identify and track a user. For example, user inputs (e.g., keyboard or mouse inputs) and/or sensor data (e.g., data from a touchscreen, pressure sensor, gyroscope, etc.) may be normalized and randomized. The normalization and/or randomization may include modifying metadata associated with user inputs or sensor data (e.g., modification of timestamps and/or modification of raw data) prior to outputting the user inputs or sensor data to an application, and/or to a service that attempts to uniquely identify users based on such metadata.