Isolated REM sleep behavior disorder (iRBD) is a prodromal marker of Parkinson's disease (PD) and related alpha-synucleinopathies. Identification of RBD is crucial for timely intervention and disease-modifying treatments. While video-polysomnography (vPSG) remains the diagnostic gold standard, its costly and resource-intensive nature limits its utility. This systematic review evaluates emerging non-PSG tools and modalities for home-based RBD detection. A systematic search of PubMed, Web of Science, and Cochrane Library identified 17 studies, categorized into actigraphy devices (n = 9), novel tools (n = 5), and emerging modalities (n = 3). Advances in actigraphy, through machine learning integration, have significantly improved RBD detection. Novel tools, including portable biopotential systems and temporary tattoo electrodes, show promise for home-based REM sleep without atonia monitoring, while contactless cameras demonstrate high sensitivity for dream-enacting behavior detection. Future studies for validation are needed, ensuring reliability and clinical applicability for large-scale screening efforts aimed at identifying individuals at risk for PD and related alpha-synucleinopathies.