We recommend using the Cradlepoint MBR95 Router because of its durability, security, and ability to work with a variety of cellular modems.
If you're using POS on the iPad, this device will allow you to create a network for your Star TSP143 LAN printer and allow you to control the cash drawer. You can get to the internet through a local area connection or through a USB 3G or 4G modem. Or even better, use both and have an always on consistent wireless connection.
So for you food trucks out there or other mobile shops, use this router with a USB modem to have a mobile register that securely processes credit cards over the Internet.