Apple Inc. released an update to the software that powers the iPhone and iPad tablet, fixing bugs that caused some customers’ smartphones to crash and implementing some design changes.

The release Monday, called iOS 7.1, adds features that will let drivers use iPhones in cars that will be available this year using Apple software. It also gives people new ways to access the Siri voice-recognition tool by holding down the device’s home button, the company said.

Last year, Apple rolled out iOS 7, the biggest overhaul of the mobile-operating system used by millions of iPhone and iPad owners. The system was revamped after design head Jony Ive took over from former software chief Scott Forstall in 2012. Customers have complained that the new version doesn’t work consistently and is prone to crashing.

The software is critical because it powers Apple’s two biggest products. The iPhone and iPad accounted for more than 70 percent of the Cupertino, California-based Apple’s revenue in its latest fiscal year.

Some other design changes in the update include darkening some colors and making it more obvious where to press buttons. The function for answering calls was also tweaked. 

For owners of the iPhone 5s, the newest high-end version of the smartphone, Apple said it also made some improvements to the TouchID fingerprint-detection technology so the device works more quickly and reliably. 

(Bloomberg)