How to hide non-editable profile fields in DrupalGap?
During hook_form_alter() implementations in DrupalGap, the form hasn't yet been rendered into the DOM, so at that point it is not yet possible to use jQuery selectors on the form.

Instead use an inline JS event (attach it to the form's prefix or suffix during the form alter). Your inline JS page event handler can have a custom function, and that custom function can do the custom jQuery selectors. Also, that appears to be the incorrect usage of the access property. Try this instead:

// During hook_form_alter()...
form.elements['field_points'].access = false;
form.suffix += drupalgap_jqm_page_event_script_code({
    page_id: drupalgap_get_page_id(),
    jqm_page_event: 'pageshow',
    jqm_page_event_callback: 'my_user_profile_form_pageshow',
    jqm_page_event_args: JSON.stringify({
        hello: 'Hi!'
    })
});


Then make a custom function:

function my_user_profile_form_pageshow(options) {
  $('#edit-user-profile-form-field-points-und-0-value').css("background-color","yellow");
  $('#edit-user-profile-form-field-points').css("background-color","yellow");
  $('#edit-user-profile-form-field-points-und-0-value').hide();
}