How to transfer contacts from any phone to a Samsung Galaxy S10 in 2 ways

Using files known as vCards, you can easily transfer contacts to your Samsung Galaxy S10 from an Android or iPhone. Here are ...

How to transfer contacts from an Android phone to an iPhone in 4 different ways

You've just purchased a new iPhone and need to transfer your contacts from an Android phone. Here are 4 different ways to do just that.
Ars Technica

Moving contacts and SMSs from a Nokia 1100 to an Android phone: is it possible?

If she's using the same SIM card, she can easily transfer contacts herself. If not and you're on AT&T, take both phones to a company-run store and they'll transfer them over for free. T-Mobile will ...