I love the headspace story and the founder Andy Puddicombe. His mission is a real one of literally "spreading awareness" to everyone.
I've had a subscription to headspace for over 3 years now(corporate discount) and used it tons when I first started to learn about meditation. However 3 years wiser, I realize that I don't need a guide and do it all myself. I forgot I was subscribed until I saw this!
Much like exercise if you don't do it everyday, you get bored of it quickly. I really enjoyed the NBA series on headspace that I would use to kick-ass at work for awhile before I finished it and nothing else seemed interesting.
I also used their sleepcasts for awhile when battling insomnia. I enjoyed them but then found myself able to fall asleep naturally because I changed my habits to work out more and would be physical tired by the end of the night.
All in all, I think headspace can truly change your life. It just depends on how you decide to go about it. Meditation, awareness, mindfulness, and many of the skills it teaches are some of the most important skills to be getting accustomed to throughout one's life. I don't think I'll ever stop meditating or practicing in my life, but I am at the point where I no longer need these apps after 3 years.