No, we don’t have to. dojox/mobile/parser is a subset of dojo.parser. Usage and how it works are basically the same. It has no mobile specific features. dojox/mobile/parser’s ONLY advantage over dojo.parser is its smaller code size. If your application unfortunately does not work with dojox/mobile/parser, you can replace it with dojo.parser. Also if you are embeding your mobile application in an hybrid container such as Cordova, the size might not matter that much and you might prefer to pick the full parser.