Your phone won't auto-pick a US carrier when you land — most foreign plans either don't include the US or roam at punitive day rates. A Roamgo eSIM swaps in a local-network data plan before you clear customs, so Apple Maps and Uber work on the curb outside JFK or LAX.
- Best for
- Business travellers landing in NYC, SF, or Austin; road-trippers needing coast-to-coast LTE; visitors who just want to skip the airport AT&T kiosk line.
- Networks
- Roams onto AT&T, T-Mobile, and Verizon (depending on the local cell tower) — the three major US carriers cover roughly 99% of populated areas with 4G LTE or 5G.
- Travel tip
- 5G works on most modern phones, but coverage is patchier in rural areas — 4G LTE is the dependable everyday speed across the country.