MTS Karnataka National Roaming Plans MTS Karnataka National Roaming Plans details are updated daily on our website www.onlinerechargeplans.co.in. MTS is an Indian Mobile Network Operator. Sistema Shyam TeleServices Limited (SSTL) is also known as Mobile TeleSystems. It is commonly referred to by the abbreviation MTS. Mobile TeleSystems is the Indian subdivision of Russian … [Read more...] about MTS Karnataka National Roaming Plans – National and International Roaming Offers