On: Live from Apple's iPad 2 event

[siglesias]

How does that account for finger size though? Children might have a hard press of the same area as my light press. Hm, could be they look at the rate of change in the growth of the tap event...but this wouldn't provide information about mass. I think it's a no go.

We need a force here. They know how heavy the iPad is. They have an acceleration. There's a force.

[Almaviva → siglesias]

The same thing happens with a real piano though: differing fingers impart different forces with the same perceived effort, yet we still manage.