INCLUSION CRITERIA:  To participate in the screening portion of this study, an individual must meet all of the following criteria:  -Has a diagnosis or suspected diagnosis of any genetically based condition causing low vision to the level specified in criteria 2.  If the genetic condition is CLN3-related, the individual must have one of the following:  Two CLN3 pathogenic variants,  One CLN3 pathogenic variant AND  clinical presentation suggestive of CLN3, OR  characteristic electron microscopy (EM) findings (such as curvilinear body, fingerprint profile, granular osmiophilic deposits).  Has an estimated visual acuity in the better seeing eye < 20/200, without the use of an assistive or augmentative device. Is between 6 to 18 years of age. To participate in the intervention/device use portion of this study, an individual must meet the above screening criteria and the following criteria: Has an appropriate cognitive developmental ability to participate based on Investigators screening assessment.  EXCLUSION CRITERIA:  An individual who meets any of the following criteria will be excluded from participation in this study:  Has any of the following auditory dysfunctions: non-reversible or non-correctable hearing loss, tinnitus that is chronic or occurring daily, auditory hallucinations that occur daily. Uses an optic-to-audio assistive device at the time or within 3 months of screening and enrollment. Is unable to travel to the NIH because of medical condition for required in-person portions of the study. Is unable to comply with or have medical conditions that would potentially increase the risk of participation.