Since the release of the iOS 7 update, I have not received text messages from iPhone users on my samsung galaxy s4. I did have an iPhone previously, but unregistered my phone with Apple when I received my new phone. I also have an iPad , but have iMessage turned off there as we'll.
No need to worry! Everything on your device is 100%. There actually is an issue with some users who've updated to iOS 7. I've been able to notice this issue first hand. The issues would relate to your friends apple devices. I recommend having one of them turn off their iMessage and retry sending you a new message. I guarantee 100% you'll be able to receive the message. Apple is currently working on an improvement, thanks!
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