To hurl - implies throwing something really forcefully, using your entire body in an exagerrated motion to generate as much power as possible.
To fling - for me, this is when you bring an object towards your body and make a short, sharp motion as if you were throwing a frisbee. Normally you fling something at someone out of annoyance. It's also a lot less controlled than a throw or a toss. You fling something in a general direction without caring where exactly it ends up.
To throw - this is just the general purpose verb form.
To toss - This is a more measured, underarm type of throw. Normally with the arm straight or nearly straight. You don't toss something very far, it's a light throw.
You would ask someone to "throw" or "toss" you the remote, but not "fling" or "hurl" you the remote.