The commissioner for this thesis was Häme University of Applied Sciences (HAMK). It consisted of planning and developing a Web Service, based on the REST-architecture. The users (including their details) and the activities (including their events) related to oldtimerTimer act as the resources for this Web Service.

The objective of this thesis was to build a layer between the mobile application and the database, through which we could easily and safely send data from one to the other. Existing methods for doing this were obscure, and lacked any kind of security or authentication.

The Web Service was implemented in Java using the REST-architecture, and it is currently running under the Glassfish Application Server. The actual data-storage-layer is running under Apache, in the form of MySQL-database. The Web Service supports the use of XML-based messages on its requests, since JSON was deemed unnecessary addition regarding oldtimerTimer at this point in time.

The development work was done using The NetBeans Software Development Platform, which had RESTful Web Services-plugin installed to it. This plugin allowed the development of RESTful Web Services using Java.

The source material for this thesis was mainly found from various different websites, including some academic ones, in the form of lecture-materials, guides and video tutorials. These materials were mainly written in English, as Finnish material was quite hard to come by. Some literature was also used, but these pieces mainly dealt with the various architectures from which the REST architecture borrows parts from, and not the actual REST architecture itself.

The service was being continuously tested during the development, using different kinds of browser-plugins (such as RESTClient and Postman) that allowed posting requests and receiving responses from the Web Service.