I have an iPod Touch 4th generation. I use iMessages a lot instead of my phone because I can type on it a lot faster than I can text, and because it offers conversation view.
Obviously I can only use it when I have a wi-fi connection. But lately, I've been noticing more and more often that it chokes, even on normal messages that don't contain a picture or video. For example, I'm currently trying to text a friend of mine who has an iPhone. She has a data plan with unlimited texting, so she is good to go. I know she has service right now because texting between our two phones works. But when I try to send her an iMessage, the progress bar gets about 3mm away from being complete, then freezes there, and after a couple of minutes, I get the "message not delivered" alert. I know I have Wi-Fi here since I'm using it to post this question. What's going on?