Helium Mobile's 1GB + 2GB plan for 2 lines costs $0 per month.
It rides on the T-Mobile and Helium network for coverage.
It includes 100 minutes, 300 texts, and 1GB + 2GB of high-speed data per month. The data is shut off after you reach your high-speed allotment. Unfortunately, you do not get any hotspot data with this plan. Video streams at 480p quality.
The Helium Mobile Zero plan has deprioritized data. Having deprioritized data means you may temporarily experience slower speeds during times when the cellular network is busy. You'll resume getting the fastest speeds available when the network is no longer busy.
Overall, I recommend the Helium Mobile Zero plan because it is a good value.
You can also check out these plans with the same coverage and data amount (scroll left and right to browse plans):