Short answer: In Jain cosmology, Simandhar Swami is a living Tirthankar (Arihant) located in Mahavideh Kshetra. He is not described as the lok sanchalak (world ruler or controller) of our Bharat Kshetra.

Key points:

• Simandhar Swami is said to reside in Mahavideh Kshetra, a region outside our Bharata Kshetra, where Tirthankaras are always present and teach. This is part of traditional Jain cosmology and scripture.
• In practice, devotees honor him as a living Tirthankar who guides souls toward liberation from that distant realm; his divya-dhwani is said to be heard by qualified yogis. This is described in classical Jain literature and in modern summaries of Samaysaar tradition.
• Śvetāmbara and Digambara traditions both acknowledge the Mahavideh Kshetra and living Tirthankaras there, though emphasis and ritual practice may vary between the traditions.

If you want a concise description from Jain sources, you can read more here and here .