diff --git a/ws/reader.php b/ws/reader.php
new file mode 100644
index 0000000..c935197
--- /dev/null
+++ b/ws/reader.php
@@ -0,0 +1,150 @@
+<?php
+
+// Lettura file di configurazione
+$config = parse_ini_file('../config.ini');
+
+// Array per la risposta del web service
+$result = [];
+
+
+switch( $_POST['op'] ){
+    case 'get-last-devices':
+        if (!empty($_POST['date_start']) && !empty($_POST['date_end'])) {
+            // Connessione al database
+            $mysqli = mysqli_connect($config['db_host'], $config['db_user'], $config['db_pass'], $config['db_name']);
+
+            // Errore nella connessione a database
+            if (mysqli_connect_errno($mysqli)) {
+                    
+                $result = [
+                    'status' => 'ERR',
+                    'message' => mysqli_connect_error(),
+                ];
+            } else {
+                // Lettura device fra le date richieste
+                $sql = "SELECT DISTINCT logs.mac, logs.ssid, logs.dbm, logs_data.received_at, devices.nome FROM logs LEFT JOIN devices ON logs.mac=devices.mac INNER JOIN (SELECT mac, MAX(received_at) AS received_at FROM logs GROUP BY mac) AS logs_data ON logs_data.mac=logs.mac WHERE logs_data.received_at BETWEEN ? AND ? ORDER BY logs_data.received_at DESC";
+                $stmt = $mysqli->prepare($sql);
+                
+                // Errore nella preparazione query
+                if (!$stmt) {
+                    $result = [
+                        'status' => 'ERR',
+                        'message' => $mysqli->error,
+                    ];
+                } else {
+                    
+                    if ($stmt->bind_param('ss', $date_start, $date_end)) {
+                        $date_start = $_POST['date_start'];
+                        $date_end = $_POST['date_end'];
+
+                        // Esecuzione statement
+                        $stmt->execute();
+
+                        $rs = $stmt->get_result();
+                        
+                        while ($row = $rs->fetch_assoc()) {
+                            // Conversione del segnale in percentuale se richiesto
+                            if ($_POST['signal_type'] == 'percent') {
+                                if ($row['dbm'] <= -100) {
+                                    $row['dbm'] = 0;
+                                } elseif ($row['dbm'] >= -50) {
+                                    $row['dbm'] = 100;
+                                } else {
+                                    $row['dbm'] = 2 * ($row['dbm'] + 100);
+                                }
+                            }
+
+                            $records[] = $row;
+                        }
+
+                        $result = [
+                            'status' => 'OK',
+                            'records' => (array)$records,
+                        ];
+                    } else {
+                        $result = [
+                            'status' => 'ERR',
+                            'message' => 'Errore durante l\'esecuzione query',
+                        ];
+                    }
+
+                }
+            }
+
+            echo json_encode($result);
+
+            $stmt->close();
+            $mysqli->close();
+        }
+    break;
+
+    case 'get-online-devices':
+        if (!empty($_POST['date_start']) && !empty($_POST['date_end'])) {
+            // Connessione al database
+            $mysqli = mysqli_connect($config['db_host'], $config['db_user'], $config['db_pass'], $config['db_name']);
+
+            // Errore nella connessione a database
+            if (mysqli_connect_errno($mysqli)) {
+                    
+                $result = [
+                    'status' => 'ERR',
+                    'message' => mysqli_connect_error(),
+                ];
+            } else {
+                // Lettura numero di device unico nell'intervallo di date
+                $sql = "SELECT DISTINCT logs.mac FROM logs WHERE received_at BETWEEN ? AND ?";
+                $stmt = $mysqli->prepare($sql);
+                
+                // Errore nella preparazione query
+                if (!$stmt) {
+                    $result = [
+                        'status' => 'ERR',
+                        'message' => $mysqli->error,
+                    ];
+                } else {
+                    
+                    if ($stmt->bind_param('ss', $date_start, $date_end)) {
+                        $date_start = $_POST['date_start'];
+                        $date_end = $_POST['date_end'];
+
+                        // Esecuzione statement
+                        $stmt->execute();
+
+                        $rs = $stmt->get_result();
+                        
+                        while ($row = $rs->fetch_assoc()) {
+                            // Conversione del segnale in percentuale se richiesto
+                            if ($_POST['signal_type'] == 'percent') {
+                                if ($row['dbm'] <= -100) {
+                                    $row['dbm'] = 0;
+                                } elseif ($row['dbm'] >= -50) {
+                                    $row['dbm'] = 100;
+                                } else {
+                                    $row['dbm'] = 2 * ($row['dbm'] + 100);
+                                }
+                            }
+
+                            $records[] = $row;
+                        }
+
+                        $result = [
+                            'status' => 'OK',
+                            'records' => sizeof($records),
+                        ];
+                    } else {
+                        $result = [
+                            'status' => 'ERR',
+                            'message' => 'Errore durante l\'esecuzione query',
+                        ];
+                    }
+
+                }
+            }
+
+            echo json_encode($result);
+
+            $stmt->close();
+            $mysqli->close();
+        }
+    break;
+}
\ No newline at end of file