> despite feature phones normally having very long battery time, this is probably not the case when using personal hotspot if you don't mind USB tethering, i'l

> despite feature phones normally having very long battery time, this is probably not the case when using personal hotspot if you don't mind USB tethering, i'll bet that's a lot more power friendly (and if the feature phone still drains fast, lets you keep it powered for as long as you need the hotspot). i think most "feature phones" nowadays run Android -- which should support USB tethering though possibly conditional on your carrier if you don't root it first.