Why can't my Android receive texts from certain iPhones?

Most of my friends have gotten the iPhone 5, and I have a Droid 4. Someone gave me her number last week and now whether I'm gonna receive a text or not is unpredictable. Like, the first 2 days I texted her I got back her messages, but after that it's all just stopped; she gets mine but I don't get hers anymore. I know she isn't just not texting back because the first time I got no response, the next day when I saw her in person she asked me if I got her text or not.

I have plenty of other friends I always get texts back from who have iPhones. The problem might be on her end, but I barely know a thing about iPhones so I wouldn't know. Also, this might even explain some other similar incidents where I haven't gotten texts back, only from iPhones. I thought it was just a normal thing, like I just wasn't texted back, but now that I know this can happen, I don't want this to turn into a serious problem.

Is it an iPhone to Android issue, or something else?

May want to check to see if person is blocked from messaging you, if she is receiving your texts it's not her phone, iPhone 5 has a feature to block incoming messages whether text or call related, if she had that on, she wouldn't receive anything from you. May want to check your manual or settings to see if your android has a similar feature like that, if problem persists I would return to retailer who sold phone to you and ask why you are only receiving a selected few messages from some friends but not others. Could be something technical they could fix.

Did you ever had an iphone? If you did you need to reset your apple id password. And for iphone user they must go to message settings and turn Send as SMS "ON"