S4 automatically turns off mobile data when phone locked
I own an S4 and I have a problem where the mobile data automatically turns off when the phone is locked so I often do not receive emails, whatsapp messages, and others as soon as they are sent. I only receive them when I unlock my phone and I see that the data package is only turned on then. I would like the mobile data to be turned on at all times even if it consumes more battery so I receive messages instantly, and I was wondering whether I could do that. Would be great if you guys can give any advice. Thanks!