It may not be the iPhone at all. It depends on how your carrier handles group (MMS) messaging. Not all carriers offer the ability to use the type of group messaging where the conversation happens in a single thread like on the iPhone. Some only offer the ability to send the same message to multiple recipients at once, but not receive responses back in the same thread, rather each message comes back in a separate(individual) thread. I know that you can do the "iPhone style" group messaging on AT&T, Verizon, and Sprint in the US. It doesn't work the same on all carriers. After you've confirmed that all your settings are set correctly, you might want to check with someone else using an Android phone on your carrier to see if they can do it.
Posted via the Android Central App