Rubber-like stretchable display

Jörg just sent me a link on a rubber-like stretchable display that is published in Nature Material. There is a previous press release with some photos [2]. This is a significant step towards new nteractive devices, such as the one suggested in the GUMMI project [3].

[1] Stretchable active-matrix organic light-emitting diode display using printable elastic conductors, Tsuyoshi Sekitani et al., Nature Materials, doi: 10.1038/nmat2459


[3] Schwesig, C., Poupyrev, I., and Mori, E. 2004. Gummi: a bendable computer. In Proceedings of the SIGCHI Conference on Human Factors in Computing Systems (Vienna, Austria, April 24 – 29, 2004). CHI ’04. ACM, New York, NY, 263-270. DOI=

HotMobile09: history repeats – shopping assistance on mobile devices

Comparing prices and finding the cheapest item has been a favorite application example over the last 10 years. I have seen the idea of scanning product codes and compare them to prices in other shops (online or in the neighborhood) first demonstrated in 1999 at the HUC conference. The Pocket BargainFinder [1] was a mobile device with a barcode reader attached that you could scan books and get a online price comparison. Since then I have seen a number of examples that take this idea forward, e.g. a paper here at HotMobile [2] or the Amazon Mobile App.

The idea of making a bargain is certainly very attractive; however I think many of these applications do not take enough into account how price building works in the real world. If the consumer gets more power in comparison it can go two was: (1) shops will get more uniform in pricing or (2) shows will make it again harder to compare. The version (2) is more interesting 😉 and this can range from not allowing the use of mobile devices in the shop (what we see in some areas at the moment) to more sophisticated pricing options (e.g. prices get lowered when you buy combinations of products or when you are repeatedly in the same shop). I am really curious how this develops – would guess the system will penetrate the market over the next 3 years…

[1] Adam B. Brody and Edward J. Gottsman. Pocket BargainFinder: A Handheld Device for Augmented Commerce. First International Symposium on Handheld and Ubiquitous Computing (HUC ’99), 27-29 September 1999, Karlsruhe, Germany

[2] Linda Deng, Landon Cox. LiveCompare: Grocery Bargain Hunting Through Participatory Sensing. HotMobile 2009.

Keynote at Pervasive 2008: Mark Billinghurst

Mark Billinghurst presented an interesting history of augmented reality and he showed clearly that camera phones are the platform to look out for. He reminded us that currently the 3D performance of mobile phones is similar to the most powerful 3D graphics cards show 15 years ago at SIGGRAPH. Looking back at Steven Feiner’s backpack [1] – the first augmented reality system I saw – can tell us that we should not be afraid to create prototypes that may be a bit clumsy if they allow us to create a certain user experience and for exploring technology challenges.

In an example video Mark showed how they have integrated sensor information (using particle computers) into an augmented reality application. Especially for sensor-network applications this seems to create interesting user interface options.

One reference on to robust outdoor tracking done at Cambridge University [2] outlines interestingly how combining different methods (in this case GPS, inertial, computer vision and models) can move location techniques forward. This example shows that high precision tracking on mobile devices may not be far in the future. For our application led research this is motivating and should push us to be more daring with what we assume from future location systems.

Mark argue to look more for the value of experience – the idea is basically that selling a user experience is of higher value than selling a service or a technology. This view is at the moment quite common – we have seen this argument a lot at CHI2008, too. What I liked with Mark’s argument very much is that he sees it in a layered approach! Experience is at the top of a set of layers – but you cannot sell experience without having technology or services and it seems a lot of people forget this. In short – no experience design if you do not have a technology working. This is important to understand. He included an example of interactive advertisement ( which is interesting as it relates to some of the work we do on interactive advertisement (there will more as soon as we have published our Mensch und Computer 2008 paper).

His further example on experience was why you value a coffee at Starbucks at 3€ (because of the overall experience) reminded me of a book I recently read – quite a good airline/park read (probably only if you are not an economist) – makes the world a bit understandable [3].
Build enabling technologies and toolkits as means to improve one’s citation count was one of Mark’s recommendations. Looking back at our own work as well as the work of the Pervasive/Ubicomp community there is a lot of room for improvement – but it is really hard to do it …

[1] S. Feiner, B. MacIntyre, T. Höllerer, and T. Webster, A touring machine: Prototyping 3D mobile augmented reality systems for exploring the urban environment. Proc. ISWC ’97 (First IEEE Int. Symp. on Wearable Computers), October 13-14, 1997, Cambridge, MA. Also in Personal Technologies, 1(4), 1997, pp. 208-217,,

[2] Reitmayr, G., and Drummond, T. 2006. Going out: Robust model-based tracking for outdoor augmented reality. In Proceedings of IEEE ISMAR’06, 109–118.,

[3] Book: Tim Harford. The Undercover Economist. 2007. (German Version: Ökonomics: Warum die Reichen reich sind und die Armen arm und Sie nie einen günstigen Gebrauchtwagen bekommen. 2006.)

Breakfast at Google in Munich

Recently Frank Spychalski (a student from Karlsruhe University 1999) contacted me and told me that he is now with Google in Munich. As we were in Munich anyway we took the chance to meet (and as the schedule was already full breakfast was the only time slot left).

The office in Munich is close to Marienplatz, the very central spot in Munich. They are currently setting up an engineering team. It looks like a great place to work. Perhaps there may be options for some of our students to do an internship in the future.

The visit at Google reminded me of the android developer challenge. The deadline is beginning of March – perhaps there is still some time to motivate some students to create something interesting…