LiquiData is a multitouch application to explore your personal movement profile and to show other people engaging places by adding photos and comments with the help of your smartphone. It can be seen as a rating system that offers people the possibility to discover new spots in an unknown surrounding e.g. during a city-visit. Although a smartphone is not necessary to interact with the system, it offers you the possibility to give insights to your movements through the city and lets you compare your mental map with the reality. For instance, this system could give guests of a hotel (lobby) the option to share their walked trails and show other visitors their favorite coffee shops or parks.

Walk through

example run LiquiData
First the user activates the LiquidData App on his smartphone and connects it with the table by placing it on the surface where a map is shown. The gathered data from the first day trip through the city »flows« on the map and makes the paths and places visible while all unvisited places stay covered by a semi transparent dark fog.
example run LiquiData
Now the user can explore the visited spots. The chosen location is connected to the smartphone with a flexible line. Other places can be chosen by moving and rotating the smartphone. The radial navigation around the smartphone allows the user to constrict the number of linked locations. Without a smartphone the users is still able to explore the paths and recommendations of other guests with less functionalities such as adding comments, trails or photos.
example run LiquiData
The user can watch the lodged material of other guests or enrich the selected point with own photos or comments.


The project was implemented during the summer term of 2011 at the University of Applied Sciences in Potsdam in the course »Graspable Maps / 2.13.5« supervised by Till Nagel.

During the beginning of the semester a keen discussion started. The public was shocked by the uncovering of Peter Warden and Alasdair Allan which discovered that apple was tracking user movements and saved them iPhone for an unlimited time. Especially in Germany, which is always a bit paranoid in terms of data gathering and tracking of individuals, a  discussion about privacy and self determination broke out. Instead of generating new negative scenarios, we rather tried to use the gathered information in a positive way. Hence we designed a rating and recommendation system that helps people to find hidden, interesting or lovely spots in unknown surroundings like a new city. Furthermore, users can compare their impressions and self conceived map of their way with the real tracking results on a geographic map.
Das Projekt

Field of Application

Primarily, LiquidData is a research project. On one hand it was an experiment for smartphone and multitouch table communication. On the other hand we wanted to challenge our daily use of the massive data we gather or produce and how we deal with them. Personal data tracking is already part of our everyday life and it seems that we can not stop this process, or can we? Should we rather manage how to deal with it to use it for our own purpose? LiquiData is questioning these paradoxes of our privacy requests and the wish to share personal information on social media.

Although, our intention was the experiment in interaction and to discuss this topic and the practical use of the project. For instances it could be used in different kinds of navigation or tourist information systems.

The hotel lobby

One of the possible scenarios could be a hotel lobby where people return daily from their trips through the city with lots of photos and impressions. Now they see their way through the city and where they have been today if they »spill out« their movement profile. With the locations on the table they are able to tag them or observe how their paths differs from other guest. In addition, the user can add comments to the location on the table to recommend or warn of a specific spot. All of the data that has been loaded on the table can be a source of inspiration for the next trips.

Interface Elemente


The smartphone functions as primary interaction device. The movement profile automatically recorded by many devices, as well as geo-located photos, are transferred to the table and displayed at their positions on the map. All the data is being transmitted by swiping it of the phone to the table.


The Snapper is the element that connects the smartphone to the multi touch table. It draws lines from the phone to the places. These locations can be browsed by rotating the smartphone. The amount of connected locations can be controlled by the circle around the Snapper.


The locations represent public spots such as restaurants, bars, clubs, etc. that were in the radius of the user. The glyph visually encodes the various content types, with the size of the bubbles representing the amount of comments, photos and ratings for the location.

Circle navigation

The radial navigation is displayed after tapping a location on the table. This element enables to browse through comments, photos and ratings by dragging the scroll bar around the circle.


The multitouch table is the central medium for the data. Every geographical information and every manual information as photos, comments and ratings are collected on the table. A user without a smartphone can passively browse through all the data to use it as a recommendation device. The dark map is hardly visible at the beginning. The data that a user loads on the table unveils the parts where the user has been. We used a liquid metaphor to make both the interaction easy to understand as well as to attract users by the playfulness of its behavior.

The prototype was developed with the Microsoft Surface I. The programming environment Processing was used for the entire application. The aesthetic and behavior of the liquid was done with the libraries GLGraphics and toxiclibs. The multitouch gestures works with the TUIO library. All the map functions and visualizations works because of Till Nagel’s Unfolding Library and TileMill. For guides on implementing TileMill with Processing, we highly recommend the Tutorial on Till Nagel’s website or this quick tutorial.

example run LiquiData

FH Potsdam

The project was done during the summer semester 2011 at the University of Applied Sciences Potsdam under supervision of Till Nagel. [ ]

Gunnar Friedrich

Bachelor student at the University of Applied Sciences

Christopher Pietsch

Bachelor student at the University of Applied Sciences and
interface designer. [ ]

Luis Grass

Bachelor student at the University of Applied Sciences and
interface designer. [ ]

David Ikuye

Master student at the University of Applied Sciences
Bachelor interaction design (HfG Schwäbisch Gmünd) and
Interaction Designer [ ]

Pierre La Baume

Bachelor student at the University of Applied Sciences and
interaction designer / information architect [ ]
Pierre La Baume | Zeppelinstraße 141 | 14471 Potsdam.

The authors are not responsible for the content of linked pages. © 2011: Christopher Pietsch, Luis Grass, Gunnar Friedrich, David Ikuye, Pierre La Baume

Creative Commons Creative Commons Lizenzvertrag

LiquiDataa project of Pierre La Baume, Luis Grass, Christopher Pietsch, Gunnar Friedrich, David Ikuye is under a Creative Commons 3.0 Unported Licence.