The goal of this diploma work is to present the design and implementation of value-added services related to an electronic messaging system called ‘Virtual Post-it’. The Virtual Post-it project, in which I actively participated for several years, was a joint project of the Budapest University of Technology and Economics and the Mobile Innovations Center.
The Virtual Post-it application is a software developed for the Maemo mobile platform. The software is capable of detecting and identifying the people nearby based on their mobile devices using Bluetooth technology. Users can send and receive location aware text and multimedia messages for each other using the system. The software includes a PyGTK based graphical user interface, which can be used with touchscreen technology. This can also be used to read or write messages.In the first part of my thesis, I will show an overview of two topics, intelligent offices and location aware services, and present briefly some related projects. After that I will inspect the details of the Virtual Post-it project, including scenarios in which it might prove to be useful. Finally, I will reveal the parts that are in need of development.
In the second part I will show the design and development phases of four new features. First of all, I have replaced the data storage system with an SQL database based new solution. I have designed the database model, while keeping the possible future developments in mind. Then I have modified the program in order to function with this brand new storage architecture. For this, I have been using the Django framework’s services. I will give a brief description of these services.
I have also created a Django based web interface to make the Virtual Post-it system more useful. The interface allows people to access their messages with a web browser from anywhere. I have also created a modern administration page for the system, where the settings and permissions of the users can easily be changed.
I have studied the cooperation of more than one Virtual Post-it devices, including the problems of storing messages at the local device or using a remote storage via the network. I have created a software environment, which is capable of storing messages in an efficient way.
I have added a new feature, which can be used in emergency situations to show the shortest escape route, and is also capable of displaying advertisements when the device is idle. For this, I will introduce a new, HTTP based network protocol. I will evaluate the alternative protocols and the choices made through the design process from different aspects.
Finally I will show some scenarios, where the Virtual Post-it system can be useful in our everyday life.