So, I just recently (2 days ago) switched from a samsung to the new iPhone 6s and I'm wondering if the phone still uses up mobile data while wi-fi is on? I know that with Samsungs, if your mobile data is on and you're connected to wi-fi at the same time, then the phone will just use wi-fi. Is it the same with iPhones? I only have 10 GB of data per month and I need it when I'm out but I've realized I don't get picture messages or group messages unless the mobile data is on. Can I leave it on as long as I'm connected to wi-fi?
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Is my iPhone using mobile data?