Need to identify web crawlers and mobile devices with your web-app ? Here is the list of couple regular expressions you can use (most common values):
Mobile Devices:
/(blackberry|motorokr|motorola|sony|windows ce|240x320|176x220|palm|mobile|iphone|ipod|symbian|nokia|samsung|midp)/i
Web Spyders:
/(google|yahoo|baidu|bot|webalta|archiver|crawler|spyder)/i
