That is how I've done it!
SLRequest *request = [SLRequest requestForServiceType:SLServiceTypeTwitter requestMethod:SLRequestMethodPOST URL:[NSURL URLWithString:@"https://api.twitter.com/1.1/friendships/create.json"] parameters:[NSDictionary dictionaryWithObjects:[NSArray arrayWithObjects:@"AnatoliyGatt", @"true", nil] forKeys:[NSArray arrayWithObjects:@"screen_name", @"follow", nil]]];
[request setAccount:[[self twitterAccounts] lastObject]];
[request performRequestWithHandler:^(NSData *responseData, NSHTTPURLResponse *urlResponse, NSError *error) {
if(responseData) {
NSDictionary *responseDictionary = [NSJSONSerialization JSONObjectWithData:responseData options:NSJSONReadingMutableContainers error:&error];
if(responseDictionary) {
// Probably everything gone fine
}
} else {
// responseDictionary is nil
}
}];