You do not need a smartphone to get live updates with a TomTom sat-nav. The built-in SIM both receives the updates and allows you to plan routes on your computer and send them to the sat-nav. I do this on my TomTom and don't have a smart phone.
It all depends what model you have.
My "Go 50" requires a connection to my phone in order to get traffic updates, etc ..... but the newer models have a built in SIM card.