for once apple is considering the lower tier users ( they havent done that in a long time )

the latest os X and ios versions will run on older hardware right down to the 4 year old 4s
and the 2007 era imacs

http://arstechnica.com/apple/2015/06/if-your-mac-or-ithing-runs-yosemite-or-ios-8-it-can-run-el-capitan-and-ios-9/

and even much more better the space requirements for ios 9 are much much lower
and it will slice and dice the apps to fit your needs

http://arstechnica.com/apple/2015/06/app-thinning-will-be-a-major-boon-for-8gb-and-16gb-iphones-and-ipads/

ios 9 for example goes from 4,9 gig to 1.2 gig

so do i