For Android phones:
To install the Caltrans QuickMap app for Android phones, you will need to allow installation of applications that aren't from Google Play (formerly the Android Marketplace).
To do this, go to Settings > Applications and make sure the "Unknown sources" option is checked.
Then, making sure you're viewing http://quickmap.dot.ca.gov/app.htm (this page) on your Android phone, download the Caltrans QuickMap app. After clicking this link and with your browser still open, touch your phone's menu button, then select "More," then select "Downloads." You will see Quickmap.apk at the top of the list of downloaded files. Touch it to begin the installation of the QuickMap app on your phone.
QR code for http://quickmap.dot.ca.gov/app.htm (this page):
The QuickMap Android app was last updated August 1, 2012.
For all smartphones:
Try the mobile web page version, making sure you're viewing http://quickmap.dot.ca.gov/mindex.html on your Internet-enabled smartphone.
QR code for mobile web page, http://quickmap.dot.ca.gov/mindex.html:
iPhone users, don't forget to save this page to your home screen.
Please be safe. Do not use the QuickMap app or mobile web page while you are driving.