Convert a Gravity Forms Text Field into a Tel Field

convert-text-field-tel-field.php

<?php
add_filter( 'gform_field_input', 'hjs_change_input_type', 10, 5 );
function hjs_change_input_type( $input, $field, $value, $lead_id, $form_id ) {
  // Replace "9" with your form ID
  // Replace "3" with your field ID
  // Replace tabindex="1" with the tabindex value of the field being overwritten
  if ( $form_id == 9 && $field->id == 3 ) {
    $input = '
		<div class="ginput_container ginput_container_text">
			<input name="input_' . $form_id . '" id="input_' . $form_id . '_' . $field->id .'" type="tel" class="medium" value="' . $value . '" tabindex="1">
		</div>';
  }
  return $input;
}