ECway Technologies provides IEEE projects and software developments with offices in multiple cities in Tamil Nadu, India. They can be contacted via phone or online. The document discusses a robust RF localization technique called Signal Strength Difference (SSD) that addresses the heterogeneity of mobile devices. SSD is proposed as an alternative to Received Signal Strength (RSS) for indoor localization. Experiments show SSD provides more robust localization when the testing device differs from the training device. SSD-based localization algorithms outperform other approaches that aim to mitigate the effects of hardware variations between mobile nodes.