Smart mobile devices (smartphones and tablets) are becoming more and more frequent, and part of our everyday lives, which leads to a growing demand for mobile applications. In order to reach the largest possible number of potential customers and to keep those same customers we need, along with today inevitable website (or portals), to have a mobile application available on as many mobile platform as possible. Developing applications for multiple platforms is quite challenging because each platform uses a different programming language and needs a large number of developers. There is also an alternative solution for the development of "native" mobile applications. They are not made by programming in native programming language, but it is installed in the same manner as conventional native applications. Thus it is possible to develop multi-platform mobile application based on web technology using HTML, CSS and JavaScript, and some free services. For the practical part of the thesis will be made one mobile application based on Web technology for the Android operating system, and with minimal changes it will be adjusted for for other mobile platforms (iOS, Symbian, BlackBerry, WebOS and Windows Phone). In this thesis will explore the advantages, disadvantages, problems and possible limitations of mobile applications based on web standards compared to a native applications. It will also explore the issue of adapting the design of the application, regardless of the dimensions of the screen that has the device.