1. A computer-implemented method, executed by at least one processor, the method comprising: obtaining a micro-blog post of a user in a crowd of users, the crowd of users being a group of users within a predefined spatial proximity to one another; obtaining a hashtag from the micro-blog post; and providing a crowd-based feature based on the hashtag from the microblog post, wherein providing the crowd-based feature based on the hashtag from the micro-blog post comprises: determining that the hashtag is representative of an interest of the crowd of users; and recording the hashtag as an interest of the crowd of users in response to determining that the hashtag is representative of an interest of the crowd of users, and wherein an aggregate profile is created for the crowd of users based on interests defined in user profiles of the users in the crowd of users, and recording the hashtag as an interest of the crowd of users comprises recording the hashtag in a separate profile maintained for the crowd of users that reflects topics of interests currently being discussed by the crowd of users.