Your phone isn't the only piece of equipment able to share an internet connection with other devices. Windows has been able to do this for years; the problem is getting it accomplished quickly, easily and wirelessly, especially on the go with a laptop system. Connectify Hotspot (two editions, various pricing) provides the tools to do precisely this, acting as a software router between whatever internet connection you provide and the other computers connected to your laptop.
The free Lite version is robust enough for most personal use and includes a simple firewall program to boot. The Pro version lets you use your laptop as a repeater and permits sharing of 3g/4g connections as well as Ethernet and Wifi, plus other benefits outlined in the vendor's comparison chart. Connectify Hotspot Pro isn't cheap however, running anywhere from $30 for an annual license to $45 for a lifetime license.
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