Citronella and shock collars do NOT take the place of training. Dogs can easily (and humanely) be taught not to jump on people without sending a jolt of electricity through their necks or sending a foul spray into their eyes, nose and mouth.
We bring dogs into our lives to be our loving companions. Would you spray or shock your kids when they were doing something you didn't want them to do? No, you would teach them the right way to do things in a loving, caring manner. Yet some folks think it's okay to do these things to their dogs. I will never understand that. If you don't want to take the time to train your dog in a loving, humane way, please, please do not get a dog.
To be perfectly honest, sprays, shock collars, prong collars, etc. are all the lazy way out for people who do not truly have the dog's best interest at heart. Afterall, it's pretty easy to just toss a collar on the dog and start zapping away than to actually take time to educate yourself on positive training methods that take a bit more time, effort and energy right? If you choose to be that person, then that is for you to live with. But please don't promote it to others as the "right" way or a "good" way to train dogs. It simply is not. Because in reality, no training is going on at all with these methods.