It's never too late Jerome, though it will depend on how much time & energy you're willing to invest. Which skills are you lacking to build a successful app business and are you ready to invest the weeks, months, possibly years of diligent work required to build them?

The mobile app space is extremely competitive these days, and frankly, ideas by themselves aren't worth much. As Derek Sivers correctly puts it, ideas are merely multipliers. Execution is worth millions. (Read http://sivers.org/multiply for more on that)

To succeed, you (or rather, your team) will need the design skills to turn your ideas into a delightful user experience and the technical skills to turn that into stable, fast, scalable apps. Those things are merely table stakes though: the toughest nut to crack is sales & marketing. Who is your audience and how will you (profitably) reach them?

Best of luck if you decide to push through with it, it's a fun ride!