@raed_saud
This is a known issue with the iOS mobile safari. Only HTML anchor tags with sms url will launch the iOS messaging application when the webapp is run in standalone mode. We have a workaround for it if a component’s Link property is set to an sms url, e.g., sms:8001234567. Following is the snippet of code from the phoneui.js library from MobiOne. You can see it creates an <a> tag in the DOM, simulates a click of the link and then removes the link.
if (href.match(/^sms:/i)) {
// Special processing for SMS URL - they do not work in standalone mode
// when set directly as window.location.href. So, we're implementing
// workaround here
var el = jQuery('<a href="' + href + '" style="position:absolute;"/>')
.appendTo(document.body);
var e = el[0];
var evt = e.ownerDocument.createEvent('MouseEvents');
evt.initMouseEvent('click', true, true,
e.ownerDocument.defaultView, 1, 0, 0, 0, 0, false, false, false, false, 0, null);
e.dispatchEvent(evt);
el.remove();