Hide Sections in Dynamics CRM

i create function named hidesection() in the OnLoad event of account entity.

function hidesection(tabName, sectionName, flag) {
Xrm.Page.ui.tabs.get("Summary_tab").sections.get("products").setVisible(false);
}

this function work fine for the web client but when i open account entity in the mobile express CRM i see error message "cannot call methode set visible of null"

can anyone help me with this issue.