Already - useful smartphones are conquering new territory , most notably the wallet . Phones can replace your credit card , driver 's license , boarding pass , keys , coupons and more . The Google Wallet app went public May 19 for Nexus 4 devices . Some new phone - wallet technology is promising but must become easier to use .
Already-useful smartphones are conquering new territory , most notably the wallet . Phones can replace your credit card , driver 's license , transit pass , keys , coupons and more . The Google Wallet app went public September 19 for Nexus S smartphones . Some say phone-wallet technology is promising but must become easier to use .