Bluetooth connection from Arduino to Android phone wont connect

Hello. I am working on an that will recieve data over bluetooth from an arduino. The problem is that i can not connect the bluetooth moduel to my phone. I am using the MLT-BT05, I can comunicate with the moduel from the arduino no problem, but i can not pair it with my android phone. I am using the OnePlus9. When I try to pair the device, the BT05 shows up under bluetooth devices on the phone, but when i try to connect its unable to pair the two devices. I have made sure trough AT commands that the BT05 is set to slave mode, and I have checked the PIN for the device to be 123456. I can connect to the device using other Apps like BlueLight and Serial Bluetooth Terminal. I have tried to connect to the device using Ketai libray but that does not work either. Here is the code from the App

import android.content.Intent;
import android.os.Bundle;
import ketai.ui.

KetaiBluetooth bt;
String info = “”;
KetaiList klist;

ArrayList devicesDiscovered = new ArrayList();
boolean isConfiguring = true;

void onCreate(Bundle savedInstanceState) {
bt = new KetaiBluetooth(this);

void onActivityResult(int requestCode, int resultCode, Intent data) {
bt.onActivityResult(requestCode, resultCode, data);

void setup() {

void draw() {
if (!bt.isDiscovering() && isConfiguring == true) bt.discoverDevices();

if (bt.getDiscoveredDeviceNames().size() > 0 && isConfiguring == true) {
ArrayList devices = bt.getDiscoveredDeviceNames();
for (int i = 0; i < devices.size(); i++) {
info += “[”+i+"] "+devices.get(i).toString() + “\n”;
text(info, width/2, height/2);
info = “”;

Is there any one out there with some tips to how i can read data from the bluetooth. Because when i connect to the device using any of the two listet Apps i can se the data I am sending from the BT05 and it can recive what i send from the App. But i need a way to get the data in to my Processing App.


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