Extensive theoretic work attempts to address the role of social norms in describing, explaining and predicting human behaviors. However, traditional methods of assessing the effect can be expensive and time consuming. In this work, we utilize data generated by the call detail records (CDRs) and geo-tagged Tweets (GTTs) as enabling proxies for understanding human activity patterns. We present preliminary results on the effect of social norms on communication patterns during different times of the day, including prayer times. Specifically, we investigate the variations in population behavioral patterns with respect to social norms between asynchronous (i.e., Twitter) and synchronous (i.e., phone calls) communication mediums in the city of Riyadh, the capital of Saudi Arabia.