Consumer Reports) -- The exploding market for applications on Google ( GOOG) Android phones, Research In Motion's ( RIMM) BlackBerry and Apple's ( AAPL) iPhone is a gold mine for developers and has resulted in a rich shopping experience for users looking to get the most out of their handheld computers. The most interesting development in apps: those that read directions and e-mail aloud to drivers. Several states have tough laws around driving and smartphone use. These new, useful applications meet the demands of folks who can't live -- and drive, apparently -- without their Android, Blackberry or iPhone. Many of these driving apps rely on GPS functions in the phones, which can be battery killers. As we have seen with battery life in the iPhone 4, HTC EVO for Sprint ( S) and the HTC Incredible for Verizon ( VZ), managing GPS and WiFi use will lead to better battery life. Consumer Reports has compiled a great list of the best and most useful smartphone apps for drivers. The editors stress that motorists should not handle phones while driving, because it could create a distraction that jeopardizes safety for themselves and for others. Using a mobile phone while driving may have legal consequences as well. Note: Consumer Reports has no relationship with the advertisers on this site.