What to do:
Use a RFID blocking wallet, purse, bag, or use RFID blocking sleeves to prevent mobile RFID skimming.
Why do it?
Have you seen a person gain access to his office by just touching his wallet to the card reader, or a lady get on the metro by tapping her purse on the ticket gantry? Similarly, a person armed with a mobile RFID reader can skim the data off your credit card in your back pocket or purse.
A RFID blocking wallet, clutch, or individual RFID blocking sleeves can prevent that. I have found that you don’t need to put the cards into the sleeves. Merely having these sleeves slotted into the wallet as the outermost layer will prevent your cards from being read.