As a professional programmer, I naturally have a keen affinity for various computer models including those that we put in our pockets.
However as a father of two, I firmly believe that computerised or televised entertainment is harmful to childrens development, and must be restricted as much as possible during formative years.
Its much too easy leave it to barney the baby-sitter to entertain the children.
I have seen how children get mesmerised my the screens and stop interacting with the rest of their under-developed senses.
So for now let him copy your behavior with preferably a wooden non-toxic imitation.
Let him develop the skills and senses that you can now take for granted.
At 18 months he's barely mastered the tactile sense, and should be experimenting with surfaces of different textures, especially with his mouth.
In years to come when the basic skills and senses are developed, he can start attaining specialised computer skills if so desired.
Baby-hacker might be a cute idea, but seeing as so many adult hackers have imbalanced development, typically below average in either social or physical development, try to lead the kid towards a balanced development.