I have a client who says that only 18% of their online sales (of a book) come from what PayPal terms, "mobile devices", which appears to be significantly lower than what his web stats indicate are mobile visitors. All things being equal, his sales should be well over 50% mobile, since well over 50% of his visitors are mobile.
Does PayPal consider tablets such as iPad and Android to be mobile devices? Or are just phones mobile devices? I cannot find anywhere where PayPal defines this.