how can I import contacts from LG phone

sync them to a compatible cloud service or your compouter, then sync them to the iphone.

Your wife should also be able to take both phones to a direct retail store for her carrier. Carriers have machines that can transfer contacts directly from one phone to another.

If your carrier happens to be Verizon (I know they sold the Extravert), there is an option on the Extravert called Back Up Assistant. As long as the phone is still active, she can sync her contacts to that. When she activates the iPhone, she can download the Verizon Cloud app and sync the contacts to the phone.