Can apps be advocacy tools? Can they change the labeling debate?

While researching information about the street light labeling debate I discovered that several apps (applications for smartphones) had been created in various countries to help consumers figure out what was in the food/drinks they were considering buying. The first ones I found were from Australia, Foodswitch, launched in January 2012 by the George Institute for Global Health based in Sydney and the Health Insurance group BUPA (an interesting partnership) and another one, The Traffic Light Food Tracker presented in September 2011 by the Obesity Policy Coalition based in Melbourne. I talked via Skype with Pr Bruce Neal who led the Foodswitch project: they do plan to develop similar apps for other countries/languages although he did not want to go into details at this point. I later found out about Fooducate and two French apps, GuidAlim and Proxiproduit launched in early 2010. Interestingly GuidAlim and Fooducate were developed by tech savvy individual entrepreneurs not by institutions concerned with obesity. Considering all those apps have reached and continue to reach significant number of people it would be worth considering what their impact is, can be. Can the app be a game changer in the debate about labeling? After all the app provides the info the industry does not want to share and the government does not dare mandating. Can such apps be used effectively by the people and communities who most need it? Can such apps become potent advocacy tools? Are the US based advocacy groups thinking about those issues?