how to go through the next arrangement? in php

Here I show a way to read it. You would have to interact within the first key of the array, as you are receiving it.

Código: Ver Demo

<?php



$arr=array(
            array(
                    array(  "estatus" => "ok", 
                            "mensaje" => "Mensaje enviado",
                            "referencia" => 2017081504081721546,
                            "numcelular" => 7711998999),
                    array(  "estatus" => "ok", 
                            "mensaje" => "Mensaje enviado",
                            "referencia" => 2017081504081737255,
                            "numcelular" => 7711279856)
            )
    );

print_r($arr);


foreach ($arr as $k=>$v)
{
    foreach ($v as $k1=>$v1)
    {
        echo "DATOS $k1<br /><br />";
        echo $v1["estatus"]."<br />";
        echo $v1["mensaje"]."<br />";
        echo $v1["referencia"]."<br />";
        echo $v1["numcelular"]."<hr />";
    }

}
?>

Resultado:

This is the array as you have it now:

   Array
(
    [0] => Array
        (
            [0] => Array
                (
                    [estatus] => ok
                    [mensaje] => Mensaje enviado
                    [referencia] => 2017081504081721546
                    [numcelular] => 7711998999
                )

            [1] => Array
                (
                    [estatus] => ok
                    [mensaje] => Mensaje enviado
                    [referencia] => 2017081504081737255
                    [numcelular] => 7711279856
                )

        )

)

This is the result of reading:

DATOS 0<br /><br />ok<br />Mensaje enviado<br />2017081504081721546<br />7711998999<hr />DATOS 1<br /><br />ok<br />Mensaje enviado<br />2017081504081737255<br />7711279856<hr />