The sector of mobile technology is the most growing in last years and so the web development has an important part, both about simple web sites and complex web applications.
Probably you heard the “responsive” word (also identified by RWD term), this term refers to provide an optimal viewing experience for all devices.
Thanks to modern languages and technologies like HTML5, Javascript and CSS is possible to make perfect web sites and apps for mobile.
Naturally the mobile web developement is complex and requires many articles to go in depth.
With this article we only show an overview without enter into many technical facts.
So here are some “fundamentals”:
Choose a framework for mobile development, it will make the job easier.
They provide components, plugins, widgets, themes etc… ready to be used so you don’t need to start from scratch.
jQuery Mobile and Sencha Touch are the most popular.
They works with modern technologies cited above.
The use of CSS3 Media Queries allows to develop layout for different resolutions.
You can test locally in the pc with various tools that emulates mobile behaviour.
You can also “convert” your own web sites and apps in native iOS, Android, Windows Phone etc… applications.
The most used tool for this purpose is Phonegap.
You can also monetize using different models: in-app ads, pay per download, freemium, notifications, paid app (see this infographic)
I also suggest these good resources for mobile web development:
The Essential HTML5 Mobile Cheat Sheet
10 handy HTML5 cheat sheets for geeks
Touch Gesture Reference Guide
iOS and Android Design Guidelines cheat sheet
How to promote an App?
Mobile Web @ W3C