Welcome to Wireless Charging 101. We have a lot to cover.

After seeing how well it worked on the Apple Watch, wireless charging has finally come to the iPhone! This is a great new feature to have, especially as more and more things support the feature in places you go on a regular basis. If you've never used anything with wireless charging before, this new ability can seem downright magical and could very well replace a cable for charging your phone at any time.

It's also going to cause some of you to alter a few behaviors you may have become accustomed to over the last few generations of iPhone. First on the list? You should really stop using the back of your case as a place to hide your cards. It's a really bad idea, and a quick way to ruin your day.

Bank cards, security tokens, really any plastic card you wave in front of an access pad or swipe at a terminal relies on different forms of magnetic transfer. Your bank cards have a magnetic stripe that can become demagnetized when exposed to a powerful magnetic force. Many security tokens and hotel room keys use RFID or NFC to transmit the secure information also rely on electromagnetic induction to function. Nearly every card you would normally carry in a wallet relies on magnets somehow, especially if you live in the US.

If you're using a wallet case for your iPhone where the cards are on the other side of the screen, there's nothing to worry about.

When you put these cards in between your iPhone and your case, using the case as a sort of one or two-card wallet, you are exposing these cards to far greater electromagnetic induction energy than they are built to handle as soon as you put your phone on a wireless charger. Your cards will quickly become useless when you put them in between your iPhone and a Wireless charger, and you won't know they are useless until you try to use them. Security tokens will simply not work, and your bank cards will no longer be able to send information.

The good news is this problem only exists between the phone and the charger. While there are a lot of wallet cases out there for the iPhone 7 that put the cards on the back of the phone, these will not be safe for your iPhone 8. The cards can not ever be on the back of the phone while the phone is on a wireless charger. If you're using a wallet case for your iPhone where the cards are on the other side of the screen, there's nothing to worry about.