The mobile segment is the fastest growing segment of Internet users. If your site is accessible via the mobile browser, you’ll notice that your mobile OS stats has been increasing rapidly. Developing with mobile in mind will improve user experience on all devices, not just phones. Whether or not you design for mobile first (http://www.lukew.com/ff/entry.asp?933), you definitely need to consider mobile performance when developing web applications.
Mobile devices may have browsers that are similar to, or even more featured, than the browsers on personal computers. Even with more advanced browsers, the devices themselves may have similar memory and bandwidth constraints to the Pentium III you were using back in 1999. While your users may be using similar applications to access your sites, the devices themselves create various constraints that you need to consider during development.
When it comes to mobile, you need to take battery life, latency, memory, and UI responsiveness into consideration throughout the development process.
Mobile users are just that: mobile. Unlike desktop computers which are tethered to the wall at all times, and even laptop computers which are generally used by stationary users, mobile users do not recharge their devices throughout the day. Mobile users expect their devices to last at least 24 hours between recharging.
While most users realize that calls and GPS usage consume battery power, ...