Upload File Objective C

- (NSString*)uploadAudio
{
    NSData *soundData = [NSData dataWithContentsOfURL:audioRecorder.url];
    NSString *urlString = @"http://twtio.com/api/upload.php?user=";
    NSString *userN = [_engine username];
    NSString *url2 = [urlString stringByAppendingString:userN];
    NSString *btwnstring = @"&tweet=";
    NSString *turl = [url2 stringByAppendingString:btwnstring];
    NSString *tpart = [tweetTextField.text stringByAddingPercentEscapesUsingEncoding: NSUTF8StringEncoding];
    NSString *finalUrl = [turl stringByAppendingString:tpart];

    NSMutableURLRequest *request = [[[NSMutableURLRequest alloc] init] autorelease];
    [request setURL:[NSURL URLWithString:finalUrl]];
    [request setHTTPMethod:@"POST"];

    NSString *boundary = [NSString stringWithString:@"---------------------------14737809831466499882746641449"];
    NSString *contentType = [NSString stringWithFormat:@"multipart/form-data; boundary=%@", boundary];
    [request addValue:contentType forHTTPHeaderField:@"Content-Type"];

    NSMutableData *body = [NSMutableData data];
    [body appendData:[[NSString stringWithFormat:@"\r\n--%@\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]];
    [body appendData:[[NSString stringWithString:@"Content-Disposition: form-data; name=\"userfile\"; filename=\".caf\"\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
    [body appendData:[[NSString stringWithString:@"Content-Type: application/octet-stream\r\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
    [body appendData:[NSData dataWithData:soundData]];
    [body appendData:[[NSString stringWithFormat:@"\r\n--%@--\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]];
    [request setHTTPBody:body];

    NSData *returnData = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
    NSString *returnString = [[NSString alloc] initWithData:returnData encoding:NSUTF8StringEncoding];

    shortTwtioUrl = returnString;
    //NSLog(shortTwtioUrl);
    return (shortTwtioUrl);
}