Buyers should prioritize high-definition (HD) camera resolution (at least 720p or 1080p) and a refresh rate of 60fps to ensure smooth, lag-free viewing. The magnification range typically spans from 2x to 32x, though some advanced models reach 64x. Additionally, look for LCD screen sizes between 3.5 to 7 inches; larger screens offer better visibility but may compromise portability. Ensure the device supports multiple color modes (e.g., high-contrast black on white, yellow on blue) to assist users with different types of visual impairments like macular degeneration or glaucoma.