Apple mooted decision to develop its own smart home products is an inevitable next step for a company that knows the kind of business growth it achieved with iPhone is unlikely to be repeated.Chasing growthThink about it like this: Smartphones have connected the planet:There are around 3 billion users in the world today.Around a third of those devices are iPhones.Global population sits at around 7.7 billion.This means that across most of the planet, if you don&t have a smartphone you probably know someone who does.It also means the rate of growth is slowing as post-adoption replacement purchasing habits take hold.