Are you more likely to use the light on your phone or an actual flashlight? Do you open your car with a car key? Randall Munroe of xckd shows how the phone is becoming a universal multi-tool.
I grate enough cheese that I'd probably try a cheese grating app.
One tool that could be added to this graph: dice. I see many young Dungeons &Dragons players using dice rolling apps instead of actual physical dice. It's unsettling for reasons I can't explain, but Douglas Adams could:
I've come up with a set of rules that describe our reactions to technologies:
1. Anything that is in the world when you’re born is normal and ordinary and is just a natural part of the way the world works.
2. Anything that's invented between when you’re fifteen and thirty-five is new and exciting and revolutionary and you can probably get a career in it.
3. Anything invented after you're thirty-five is against the natural order of things.