connector-telephony/crm_phone/view/crm_lead.xml

<?xml version="1.0" encoding="utf-8"?>
<!--
  Copyright 2014-2018 Akretion France
  @author: Alexis de Lattre <alexis.delattre@akretion.com>
  License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
-->

<odoo>


<record id="crm_case_form_view_leads" model="ir.ui.view">
    <field name="name">crm_phone.crm_lead.form</field>
    <field name="model">crm.lead</field>
    <field name="inherit_id" ref="crm.crm_case_form_view_leads"/>
    <field name="arch" type="xml">
        <div name="button_box" position="inside">
            <button class="oe_inline oe_stat_button" type="action"
                name="%(crm_phone.crm_phonecall_action)d"
                icon="fa-phone"
                context="{'search_default_opportunity_id': active_id}">
                <field string="Calls" name="phonecall_count" widget="statinfo"/>
             </button>
        </div>
        <field name="mobile" position="attributes">
            <attribute name="widget">phone</attribute>
        </field>
    </field>
</record>

<record id="crm_case_form_view_oppor" model="ir.ui.view">
    <field name="name">crm_phone.case.view_opportuniy.form</field>
    <field name="model">crm.lead</field>
    <field name="inherit_id" ref="crm.crm_case_form_view_oppor"/>
    <field name="arch" type="xml">
        <div name="button_box" position="inside">
            <button class="oe_inline oe_stat_button" type="action"
                name="%(crm_phone.crm_phonecall_action)d"
                icon="fa-phone"
                context="{'search_default_opportunity_id': active_id}">
                <field string="Calls" name="phonecall_count" widget="statinfo"/>
             </button>
        </div>
        <field name="mobile" position="replace"/>
        <field name="phone" position="after">
            <field name="partner_address_mobile"
                attrs="{'invisible': [('partner_address_mobile', '==', False)]}"
                readonly="1"
                widget="phone"
                string="Mobile"/>
            <field name="mobile"
                attrs="{'invisible': [('partner_address_mobile', '!=', False)]}"
                widget="phone"/>
        </field>
    </field>
</record>


</odoo>