Why can’t I use this for studio work anymore

After spending nearly a thousand pounds to upgrade my iPad to pro I find apple iPad Air 2 works better for my needs because it has an aux in. Why have apple sold out their musician base? I can’t use my irig to connect my condenser mic. I can’t plug into a desk. I teach singing and I need this to function like a workhorse. Where is the aux in and why is there no connection to provide that function? The headphone jack doesn’t allow input only output. Musicians are professionals too. Please do you have an option for aux in?