kindle paper while for reading
chrome book for math online etc... we use it for most online work at home. but some times i feel i need a windows 10 laptop..
ipad for dream box ixl etc when on road also some ibooks from MCT
also i have a cheap desktop to play MUS and Teaching textbooks
each of them when used carefully lasts abut 4-5 years
My desktop from 2006 kindle and ipad 2 plus
chrome book is a refub one about 3 years i think