As of version 4.0 it is possible to scroll the rows with the keys.
To do this it is necessary to call the bindKeys javascript method. See code.

Also it is possible to define some events on Enter and a Spacebar key s.
For more details refer to the documentation.

<?php 
require_once '../../../../php/demo/tabs3.php';
?>
<!DOCTYPE html>
<html>
  <head>
    <title>jqGrid PHP Demo</title>
    <!-- The jQuery library is a prerequisite for all jqSuite products -->
    <script type="text/ecmascript" src="../../../../js/jquery.min.js"></script> 
    <!-- We support more than 40 localizations -->
    <script type="text/ecmascript" src="../../../../js/trirand/i18n/grid.locale-en.js"></script>
    <!-- This is the Javascript file of jqGrid -->   
    <script type="text/ecmascript" src="../../../../js/trirand/jquery.jqGrid.min.js"></script>
    <!-- This is the localization file of the grid controlling messages, labels, etc.
    <!-- A link to a jQuery UI ThemeRoller theme, more than 22 built-in and many more custom -->
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/css/bootstrap.min.css"> 
    <!-- The link to the CSS that the grid needs -->
    <link rel="stylesheet" type="text/css" media="screen" href="../../../../css/trirand/ui.jqgrid-bootstrap.css" />
    <script>
        $.jgrid.defaults.width = 780;
        $.jgrid.defaults.responsive = true;
        $.jgrid.defaults.styleUI = 'Bootstrap';

    </script>
    <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/js/bootstrap.min.js"></script>
    <meta charset="utf-8" />
    </script>
     
  </head>
  <body>
    <div style="margin-left:20px">
          <?php include ("grid.php");?>
      </div>
      <br/>
      <?php tabs(array("grid.php"));?>
   </body>
</html>

grid.php.
<?php
require_once '../../jq-config.php';
// include the jqGrid Class
require_once ABSPATH."php/PHPSuito/jqGrid.php";
// include the driver class
require_once ABSPATH."php/PHPSuito/DBdrivers/jqGridPdo.php";
// Connection to the server
$conn = new PDO(DB_DSN,DB_USER,DB_PASSWORD);
// Tell the db that we use utf-8
$conn->query("SET NAMES utf8");

// Create the jqGrid instance
$grid = new jqGridRender($conn);
// Write the SQL Query
$grid->SelectCommand 'SELECT OrderID, OrderDate, CustomerID, ShipName, Freight FROM orders';
// Set output format to json
$grid->dataType 'json';
// Let the grid create the model
$grid->setColModel();
// Set the url from where we obtain the data
$grid->setUrl('grid.php');
// Set some grid options
$grid->setGridOptions(array(
    
"rowNum"=>10,
    
"rowList"=>array(10,20,30),
    
"sortname"=>"OrderID",
    
"userDataOnFooter"=>true,
    
"footerrow"=>true
));
// Change some property of the field(s)
$grid->setColProperty("OrderDate", array(
    
"formatter"=>"date",
    
"formatoptions"=>array("srcformat"=>"Y-m-d H:i:s","newformat"=>"m/d/Y"),
    
"search"=>false
    
)
);
$grid->setColProperty("ShipName", array("width"=>"200"));
// Enable navigator
$grid->navigator true;
// Enable excel export
$grid->setNavOptions('navigator', array("excel"=>false,"add"=>false,"edit"=>false,"del"=>false,"view"=>false));
// Enjoy
// Set summary field
$summaryrows=array("Freight"=>array("Freight"=>"SUM"));

// and finaly bind key navigation
// This is way if no events or parameter
//$grid->callGridMethod('#grid', 'bindKeys');
//
//in case of passing events is better this way

$bindkeys =<<<KEYS
$("#grid").jqGrid('bindKeys', {"onEnter":function( rowid ) { alert("You enter a row with id:"+rowid)} } );
KEYS;
$grid->setJSCode($bindkeys);

$grid->renderGrid('#grid','#pager',true$summaryrowsnulltrue,true);