For a long time, it was accepted wisdom that each successive generation would be better off than the last. We’re talking about many, many generations where this was true. Things have changed dramatically over the past few decades.
And while the mobile sector is hot right now, there is no guarantee that in some years’ time, the desire or ability to do more with mobile devices will fade away, and you may well find yourself in that unenviable position of being in your 50s and trying to compete with the younger generation for jobs that you are not trained for and in which you have no experience. Even if you do have experience, good luck competing with someone who doesn’t have a family or other obligations…one who is willing to work twice the number of hours for half the money as you were making in your prior job.
Not that long ago, people with Liberal Arts degrees were also being pinged by headhunters on a very regular basis. Many of them thought they were invincible, and that their opportunities would only grow with their experience, knowledge, and a strong business network. It’s always best to look at the bigger picture, IMHO.