The ETravelSim Switzerland eSIM runs on Swisscom — the country's largest mobile operator and the network independently rated as Switzerland's gold standard for coverage, particularly in rural and mountain regions. Swisscom has the most extensive national footprint compared to Sunrise (strong in cities) and Salt Mobile (third-largest). For Alpine ski trips, mountain hikes, scenic train routes, and rural exploration, Swisscom is the network most travelers actually want.