I wish it was that simple. First there is battery life and surprisingly some foreign carriers block tethering features like Personal Hotspot. As an example a SI

I wish it was that simple. First there is battery life and surprisingly some foreign carriers block tethering features like Personal Hotspot. As an example a SIM card I've got from Softbank in Japan in 2014 only allowed me to connect to their network after I've installed a profile that disabled tethering.