A system for testing an individual for illicit or other substances is described. The system operates in tandem with a mobile device (smartphone) application, which employs a camera of the mobile device to capture and record the self-administered specimen collection process for verification and rule compliance. The system guides the user through the process via on-screen prompts on the mobile device, and includes tracking of the collected specimen from the moment of collection until it is sealed in a tamper-proof container to be mailed for external testing at a lab. A breathalyzer may also be used with the system to test for the presence of alcohol in the user's body, the use of which is also monitored and recorded via the on-board camera of the mobile device for verification.