Verizon and AT&T offer data plans in several tiers starting from 300 MB to up to 100 GB, as of October 2015. Many of these data plans come with unlimited calls and texts within the United States. Data allowance can be shared with family members and across different devices.
It is difficult to determine how each Internet activity affects a customer's data usage, states Verizon Wireless. The company provides its customers with monitoring tools, such as usage alerts, real time data usage meters and a data utilization tool.
The AT&T website features a smartphone data calculator to let customers estimate the amount of data each Internet activity consumes.