P. Metaxas, E. Mustafaraj, K. Wong, L. Zeng, O. Keefe et al., Do Retweets indicate Interest, Trust, Agreement? arXiv preprint arXiv, p.14113555, 2014.

P. Cofta and . Distrust, The new e-commerce: innovations for conquering current barriers, obstacles and limitations to conducting successful business on the internet, Proceedings of the 8th international conference on Electronic commerce, pp.250-258, 2006.

N. Marres and E. Weltevrede, SCRAPING THE SOCIAL?, Journal of Cultural Economy, vol.21, issue.3, pp.313-335, 2013.
DOI : 10.1177/0038038508099104

M. Kelley, The Impact of Fitness Technology on Health Outcomes, 2014.

D. Conroy, C. Yang, and J. Maher, Behavior Change Techniques in Top-Ranked Mobile Apps for Physical Activity, American Journal of Preventive Medicine, vol.46, issue.6, pp.649-652, 2014.
DOI : 10.1016/j.amepre.2014.01.010

M. Clayman, J. Manganello, K. Viswanath, B. Hesse, and N. Arora, Providing Health Messages to Hispanics/Latinos: Understanding the Importance of Language, Trust in Health Information Sources, and Media Use, Journal of Health Communication, vol.8, issue.11, pp.252-263, 2010.
DOI : 10.1080/108107300406857

U. Albrecht, Transparency of Health-Apps for Trust and Decision Making, Journal of Medical Internet Research, vol.15, issue.12, pp.277-277, 2012.
DOI : 10.2196/jmir.2981

J. Kim and S. Kim, Physicians' perception of the effects of internet health information on the doctor???patient relationship, Informatics for Health and Social Care, vol.282, issue.3, pp.136-148, 2009.
DOI : 10.1080/17538150903102422

J. Golbeck, Generating Predictive Movie Recommendations from Trust in Social Networks, Tavakolifard M, Almeroth KC (2012) THE HIDDEN TRUST NETWORK UNDERLYING TWITTER. On Some Challenges for Online Trust and Reputation Systems, p.79, 2006.
DOI : 10.1007/11755593_8

B. Suh, L. Hong, P. Pirolli, and E. Chi, Want to be Retweeted? Large Scale Analytics on Factors Impacting Retweet in Twitter Network, 2010 IEEE Second International Conference on Social Computing, 2014.
DOI : 10.1109/SocialCom.2010.33

S. Finn, P. Metaxas, E. Mustafaraj, O. Keefe, M. Tang et al., A system for monitoring the propagation of rumors on twitter, Computation and Journalism Symposium, 2014.

C. Castelfranchi and R. Falcone, Trust theory: A socio-cognitive and computational model, 2010.
DOI : 10.1002/9780470519851

M. Kranz, A. Möller, N. Hammerla, S. Diewald, T. Plötz et al., The mobile fitness coach: Towards individualized skill assessment using personalized mobile devices, Pervasive and Mobile Computing, vol.9, issue.2, pp.203-215, 2013.
DOI : 10.1016/j.pmcj.2012.06.002

URL : http://mediatum.ub.tum.de/doc/1197602/document.pdf

A. Mcneill and P. Briggs, Understanding Twitter influence in the health domain, Proceedings of the 23rd International Conference on World Wide Web, WWW '14 Companion, pp.673-678
DOI : 10.1145/2567948.2579280

G. Padmasekara, Fitness apps, a Valid Alternative to the Gym: a pilot study, Journal of Mobile Technology in Medicine, vol.3, issue.1, pp.37-45, 2014.
DOI : 10.7309/jmtm.3.1.6

D. Yoganathan and S. Kajanan, Persuasive Technology for Smartphone Fitness Apps, 2013.

D. Riff, S. Lacy, and F. Fico, Analyzing media messages: Using quantitative content analysis in research. Routledge, 21. See-To EW Value co-creation and purchase intention in social network sites: The role of electronic Word-of-Mouth and trust?A theoretical analysis, Computers in Human Behavior, vol.31, pp.182-189, 2014.

R. Waters and J. Jamal, Tweet, tweet, tweet: A content analysis of nonprofit organizations??? Twitter updates, Public Relations Review, vol.37, issue.3, pp.321-324, 2011.
DOI : 10.1016/j.pubrev.2011.03.002

E. Sillence, P. Briggs, L. Fishwick, and P. Harris, Trust and mistrust of online health sites, Proceedings of the 2004 conference on Human factors in computing systems , CHI '04, pp.663-670, 2004.
DOI : 10.1145/985692.985776

P. Verbeek, Moralizing technology: Understanding and designing the morality of things, 2011.
DOI : 10.7208/chicago/9780226852904.001.0001

R. Hardin, Trust and trustworthiness, 2002.

M. Frederiksen, Trust in the face of uncertainty: a qualitative study of intersubjective trust and risk, International Review of Sociology, vol.5, issue.1, pp.130-144, 2014.
DOI : 10.1023/A:1010690908200