A subscription costs $20 per month for unlimited calls and messaging, plus a customizable data allowance costing an additional $10 per gigabyte. Money for unused data is credited back to the user's account, and overuse of data costs an additional $10 per gigabyte. A group plan costs an additional $15 per user per month, and offers features including data overview, data notifications, monthly allowances, and the ability to pause users' data usage. A data-only SIM card can be used on supported tablets, smartphones, and car modems (e. g. , Volvo). A Data-only sim will have access to data, but will not be able to make calls or transmit texts across cellular networks .