Example,
OACredential *credential = [[objc_getClass("OACredential") alloc] init];
[credential setConsumerSecret:@"TWITTER_SECRET"];
[credential setConsumerKey:@"TWITTER_KEY"];
[credential setOauthTokenSecret:@"TWITTER_TOKEN_SECRET"];
[credential setOauthToken:@"TWITTER_TOKEN"];
OAURLRequestSigner *signer = [[objc_getClass("OAURLRequestSigner") alloc] initWithCredential:credential];
[signer setSignatureMethod:0];
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL:[NSURL URLWithString:@"https://api.twitter.com/1.1/statuses/update.json"]];
NSData *data = [@"status=thanks @moeseth" dataUsingEncoding:NSUTF8StringEncoding];
[request setHTTPBody:data];
[request setHTTPMethod:@"POST"];
request = [signer signedURLRequestWithRequest:request];
[NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {
NSLog(@"data -> %@", [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding]);
}];