JavaScript and HTML5 capabilities of modern smart phones provide interesting possibilities for the creation of mobile semantic solutions. The talk introduces two approaches to create Topic Maps based mobile applications with JavaScript. The first part describes the prototype of a generic textual Topic Maps viewer for both iPhone and Android. It can be used to browse topic maps stored on the device or downloaded from the internet. The second part of the talk presents a way to visualize a topic map with spatial information in an augmented reality browser. The topic map itself resides on a server written in JavaScript with nodejs and is transfered to the client using the Augmented Reality Markup Language (ARML).