S-IMSY provides a SIM and a portal (you can also develop your own service using APIs) which when connected to your HA device via an integrated cellular modem or a USB cellular dongle allows you to remotely connect to your device.
Let me guess: US only?
Nope, doesn’t look like the US is even an option.
Hi Francis, its not restricted to US, in fact its available in most countries bar the US, which is coming soon. Which country/countries would you require coverage in? New networks are being added regularly.