Only th developer of the app can make tht possible, unlike with the old nokia express music etc u wld choose but all sd card apps wld freeze th moment u connected with a usb, if its developed to install in th internal memory only, u cant change tht and this is for a reason, like for whatsapp, its an app which evrybdy nds to run continuosly, hwever if u wld install it to th sd card, the app wld likely be unavailable th moment u connect yo phone to pc as media storage or myb u jus charging usin a usb cable... How invonvenient wld tht b