iOS - Wireless Communication Lagging - ios

Question

So I'm making a game that involves wireless communication between multiple iPhones, with one being the host. I am attempting to do so via the MultipeerConnectivity framework, and I've made a MCManager class (an instance of which I put into appDelegate so it's available throughout the app) to handle sending data from one system to another. This is how sending is implemented in my code:
- (void) sendState: (NSString*) str;
//used by the host to send commands to the other connected systems
{
if(appDelegate.mcManager.connected && iAmHost){
NSData *dataToSend = [str dataUsingEncoding: NSUTF8StringEncoding];
NSArray *allPeers = appDelegate.mcManager.session.connectedPeers;
NSError *error;
[appDelegate.mcManager.session sendData:dataToSend
toPeers:allPeers
withMode:MCSessionSendDataReliable
error:&error];
if (error) {
NSLog(#"%#", [error localizedDescription]);
}
}
}
and when the subordinate systems receive the data, MCManager sends the Notification Center a notification and my class, which is looking for that particular notification, grabs it and executes this:
-(void)didReceiveDataWithNotification:(NSNotification *)notification{
if(!iAmHost){
NSData *receivedData = [[notification userInfo] objectForKey:#"data"];
NSString *action = [[NSString alloc] initWithData: receivedData encoding:NSUTF8StringEncoding];
NSLog(#"Recieved:");
NSLog(action); //for debugging purposes, and figuring out timing
//decide how to act depending on the string given
if([action containsString:#"ChangeMaxScore"]){
//the string was formatted as, for example, "ChangeMaxScore105"
NSString* valueStr = [action substringFromIndex:14];
maxScore = (int)[valueStr integerValue];
[self changeMaxScore]; //this method changes the label text that shows the user the value of maxScore
}
else if([action containsString:#"ChangePlayerNo"]){
//strings are formatted as "ChangePlayerNo2" for the second segment in a segmented control with the segments "2", "3", "4"
//so it would be referring to four players
NSString *valueStr = [action substringFromIndex:14];
[playerNumberSegmentedControl setSelectedSegmentIndex: [valueStr integerValue]];
playerNumber = playerNumberSegmentedControl.selectedSegmentIndex + 2;
[self changePlayerNumber];
//Players can either be human or a type of AI (AI-1,AI-2,etc.)
//the segmented control where you choose this is invisible unless that player number is playing
//so this method sets that segmented control visible and interactable (by adding it to the view)
//and removes those segmented controls not in use from the view
}
else if([action containsString:#"ChangeP0State"]){
//changes the value of the first player's segmented control (Human, AI-1, AI-2, etc.
NSString* valueStr = [action substringFromIndex:13];
AIControl0.selectedSegmentIndex = (int)[valueStr integerValue];
}
...
else if([action containsString:#"StartGame"])
[self newGame];
//this method starts the game and, in the process, pushes another view controller
}
}
My issue is that these actions, on the receiving end, are very laggy. For changing the number of players, for instance, the receiver NSLogs "Received: ChangePlayerNo1", and the segmented control on-screen changes its selected segment to the second one, but the stuff that's supposed to show up at that point...doesn't. And when I send the "StartGame" command, the receiver NSLogs that it has received it, I have to wait thirty seconds for it to actually start the game like it was asked.
This delay makes it very hard to test whether my wireless methods are working or not (it works on the host's side, mostly because the host is changing them manually, not responsively - also, all of this works on the other side of my program, which is just the game without wireless support, with several players/AIs on a single screen) and, if not fixed, will definitely prevent the app from being used easily.
I'm curious what causes this and what I can do to fix it. Thank you!