As you know 'GlideScriptRecordUtil' is not allowed in Scoped Apps, we can user below function to get changed fields on server side
//this will give you array of changed field names var changed _fields = getChangedFieldNames(current); function getChangedFieldNames(gr) { var result = []; var elements = gr.getElements(); var size = elements.length; for (var i = 0; i < size; i++) { var ge = elements[i]; if (ge.changes()) { result.push(ge.getName()); } } return result; }