getContextForAddress.m

// get advanced demographic information for an address

SGContextQuery *query = [SGContextQuery queryWithAddress:@"41 Decatur Street, San Francisco, CA"];
[query setFilters:[NSArray arrayWithObject:SGContextFilterDemographics]];
[query setACSTableIDs:[NSArray arrayWithObjects:@"B05005", @"B06009", @"B07001", nil]];

[client getContextForQuery:query
                  callback:[SGCallback callbackWithSuccessBlock:
                            ^(id response) {
                                // you've got demographics!
                            } failureBlock:^(NSError *error) {
                                // handle failure
                            }]];