Q: imessage lag

Hi there hcouv,

You may find the information in the article below helpful.

iOS: Troubleshooting Messages

http://support.apple.com/kb/ts2755

If you still can't send or receive an iMessage, follow these steps

1. Make sure that the contact trying to message you isn't blocked in Settings > Messages > Blocked.
2. Make sure that the contact you're trying to send a message to is registered with iMessage.
3. If the issue occurs with a specific contact or contacts, back up or forward important messages and delete your current messaging threads with the contact. Create a new message to the contact and try again.
4. If the issue occurs with a specific contact or contacts, delete and recreate the contact in the Contacts app. Create a new message to the newly created contact and try again.
5. Back up and restore your device as new.

-Griff W.