[vacri]

By 'usable', do you mean that your one year old child can browse the app store, find something they like, install it, and use it?

At a new location, can they identify the correct wireless network to use, and enter the password?

Or do they just use an easy subset of what the ipad offers? We don't go "Wow! the toy piano is easy enough for a toddler to use!" and gush over it, because we know the toddler isn't using the piano like some virtuoso.