Traditional approaches to recording deep brain activity in humans require participants to remain immobile, limiting the ecological validity and breadth of cognitive neuroscience questions that can be asked. Individuals with neurostimulator devices that are chronically implanted for clinical purposes present a rare opportunity to record intracranial electroencephalography (iEEG) from the human brain while participants are mobile and interacting with their environment in a natural way. Research-related benefits of such chronic neurostimulator devices include resistance to motion artifacts, access to deep brain structures, measurement of neural activity with high temporal resolution, as well as the possibility to perform closed-loop neuromodulation through stimulation that can be associated with specific behavioral or neurophysiological features. Furthermore, recent technical developments have streamlined the integration of numerous wearables with wireless iEEG recordings, including virtual and augmented reality headsets, which substantially broadens the scope of possible cognitive neuroscience experiments that can be implemented. Here, we provide an overview of the methodological and technical aspects of mobile iEEG recordings in human research participants and discuss associated promises and challenges. With this overview, we aim to inspire innovative future applications of mobile iEEG to advance our understanding of rich human behaviors in health and disease.