public function get($appId)
    {
        if (ArrayOperations::checkNull([$appId])) {
            throw
            new PlivoValidationException(
                'app id is mandatory');
        }

        $response = $this->client->fetch(
            $this->uri . $appId . '/',
            []
        );

        return new Application(
            $this->client,
            $response->getContent(),
            $this->pathParams['authId']);
    }