3G Question

When using my iPhone 3Gs on the regular network speeds we get around these parts the battery will last all day and then some.

When I am able to connect to the 3G network the battery like is significantly reduced. Like about 30% of what it usually gets.

Is this a common issue? Or feature...

Fairly common. The iPhone 4(and later) seems to have fixed the 3G problem - meaning even if you keep 3G on the iPhone 4 will last all day (usually) Back when I had a 3G iPhone - I remember shutting of 3G unless I knew I was going to use it.

Now of course the iPhone 5 is running 4G - still lasts a good while but it seems if you turn off 4G you'll get longer battery life.

Same with the iPad 3. Keeping 4G LTE on cuts battery life in half.