My phone’s network capabilities depend on the chip(?) made by simcom. I currently have one that allows for 2g (2nd generation) network connections. I need to get one that allows for 3g or 4g. This piece is made by simcom. Adafruit sells one that is already connected to a board. It is more expensive. I should look into learning more about this part and maybe making my own PCB to lower the cost on this piece.
Here is the option I purchased today: https://www.modmypi.com/raspberry-pi/communication-1068/raspberry-pi-sim800-gsm-breakout-board
I will need to follow this tutorial once it arrives: https://www.modmypi.com/blog/how-to-connect-your-raspberry-pi-to-a-3g-network
Here is the more expensive adafruit version: https://www.adafruit.com/product/2691
Here is a cheaper option: https://www.amazon.fr/Sim800l-Quadribande-Embarqu%C3%A9e-Antenne-Arduino/dp/B01FQPLG9W/ref=sr_1_1?ie=UTF8&qid=1504798267&sr=8-1&keywords=SIM800