You don't actually need it to fly but you are missing the majority of the fun if you can't see through the camera.
You don't need a smartphone on a network, you have to initially activate online - use wifi at home - then can stay offline for evermore if you want.
A basic smartphone can be had new under $100 it's nothing to be scared of - and very useful.Alternatively consider a small tablet.
They do need to be a reasonably powerful model as the app is quite demanding.