Can I use an iPad charger with my iPhone 4?
The iPhone simply won't draw as much through the charger as the iPad would. Certainly shouldn't cause a problem at all (and my money's where my mouth is because we just have the iPad charger plugged in these days, using it for our iPad as well as our 2 iPhone 4s - we've been doing this for about 5-6 weeks now without any obvious ill-effects).