Awesome! One of the best ESP32 BLE video on youtube

FIX for people having issue with sending data from app to esp32: I followed every step (nice job mate), but my app was crashing with no error whenever I tried to send data (after changing the slider position). So I've tried different things, apparently what works is to stick with only one characteristic, add the write and read property and the callback to it, and of course use the same UUID for both receiving and sending functions in the app inventor. Do know why, maybe it's my cheap phone, but it worked for me

Crikey! That was very very good. Thanks very much for sharing your knowledge in this very clear and concise video.

Thanks a lot from Turkey. Explanation is really good. I really appreciate your works..

An absolutely indispensable guide, expertly explained! Thank you. (Just to show that I was paying attention -- and I hesitate to mention it -- but 2^16 is 65,536, not 56,536).

You are the goat. You just saved us so much time and it actually worked.

Thanks so much! Big help in learning how to do this. My project is for an automotive security product.

Good tutorial. The APP is available in MIT app Inventor Gallery?

Very good and interesting explanation! I am just working on Smartphone connected to ESP32 to open Garage door as for exchange an old remote control!

Tested on ESP32-WROOM-32 (Mini D1 ESP32) and Samsung S23+ today. Works fine for me. Thank's for this great tutorial!

Very good video, you have some to send text from the phone to esp32

Well this series is going amazingly! I've found your channel because I was looking for exactly this, a mobile app that communicates with esp32! Since I didn't expect for you to make just what I needed I launched myself into doing an app of my own in ReactNative, which works fine, but... I'm actually having a problem with the communication, and since you did this tutorials I think you probably can help me or at least point me in a direction that leads to an answer: Using your previos video example (the BLE sending a increasing number) I've modify it a bit so it reads a sensor value that goes from -127 to 127, and it works fine until the sensor (correctly sensing, btw) reads many data together, but never as fast as the 3ms that the example code says. The thing is, when it happens, the esp32 freezes and stops. Only a reset un-freezes it. Do you happen to know what could be? It's not the sensor because without the BLE it never happens.. Thanks a lot for the time you take in doing this guides, I really love them!!

Thanks so much!

Just something to note and I may have missed you covering it, is that BLE scan doesn't work unless you allow MIT App Companion permission to access your precise location! At least on a Pixel 5. Even the Emulator didn't work until I clicked on allowing location permission. The permission request may have flashed on the screen but only briefly. Please keep up the good work with your excellent videos. I am trying to use your code as a basis for a small 6V solar panel meter using an ESP32-C3 although about to modify my board due to a tiny screwup with the voltage supervisor.

First of all, thanks for such a great video. It is very helpful to understand from the scratch. I have a question. It seems like that the App will disconnect with ESP32 after awhile (phone screen off awhile). I have to re-scan and connect to ESP32. Is it possible to keep it connected? Thank you so much!

Muy bueno el video,tienes alguno de mandar texto desde el teléfono al esp32

First let me thank you for a great tutorial, my question is, I have been working with the bluetoothserial library and wondered if this project could be adapted for it?

Thank you for this great series. I wonder if it is possible to use this same ESP board as a client simultaneously. I mean, in this same system the ESP32 will get sensor readings from another BLE device (server) and send it to mobile app. Although I am not expert, this may be possible with multitasking via FreeRTOS. Another small demonstration of this would be great.

Once again, very clear and helpful. In my project I am trying to switch (in the client,) between the data feeds from 2 connected BLE servers. It seems to be possible? If I understand correctly there can be many connected servers at once, depending on chipset used and memory, etc?

I'm very happy for discover yours videos, Thank you for a graet contribution. Do you know if is possible using this app or esp32 conect direct to a smartband to get data from heart beat? thank in advanced...

Good job bro. Thank you very much. I'm following. The eyes are a little weak, I hope I can handle it. Good luck. Greetings at friends who follow you

Hi, great video. I want to send a text from android app to BLE, how to setup translate from bytes to text on MIT app inventor ? All i recieve is a array of decimal number but i cant find a way to process them in MIT app.

Hi great video, it is veru helpfull for me , I'm doing a little rc car, it is really small so im using the xiao esp32, but the BLE dfficult to make an application

First, BIG thank you! just what I needed, or almost. Now the question of course. What if you have two sliders p.e. that send data (not together of course). I see nowhere in the CharacteristicCallBack class a way to differentiate between UUID's of chars from the app.

@7:40 Could you please mention the reason for adding a custom permission name in the form of a text "BLUETOOTH_CONNECT". I see that the inbuild permission name list also have a permission name "BluetoothConnect". Could you please clarify on why that was not used. Thanks in advance.

Thanks for posting, this is a tremendous help to my project.

Thanks a lot for this. I have an ESP32 which measures a few data points and I want to log it to a CSV file. I was thinking about ESP32 with a SD card reader, but I rather transfer the data over BT to have the phone log the data into CSV. My values will be float values but only with 1 decimal place precision, therefore I was considering pushing them over as integers. All my values should fit into 2 bytes and I can easily split them up in the app. I did not watch you first video, I hope that explains how to define what data type a characteristic is. Or that is always assumed to be byte list? I assume there is an option to install the app permanently on the phone eventually.

Great video! Could you please suggest the way to plot the receiving BLE data?

Thank you for this great series, I want know will it work with ESP32 WROVER IE ? I have tried with ESP32 WROVER IE but not able to connect with ESP32. I could get data on nRF Connect & BLE Scanner App.

Thankyou for this videos. I want to ask question, recently I am trying to build a project in which I am using BLE sensor known as TPMS(Tire Pressure Monitoring System) with ESP32 or Arduino Uno. If i use ESP 32 then how can i see the uuid of the BLE sensor? . Also If i used Arduino Uno then I have to used Bluetooth module which has different programming as compared to ESP32. I only need to know how can i captured the data from the BLE sensor ? IF you can assist me in this I will be very thankful for you. :)

if I want to transmit bytes and then drive the motor to rotate. How should I do this? Thankyou

what if you dont know the uuids of the device you connect to? edit: ok nvm, I just watched your other BLE videos, all clear, thank you for the videos!

Hi Mo, You ask for our projects. I'm creating a control for a greenhouse in which mushrooms will grow. Thank you for your educational videos. They are very clear and understandable. ciao Joerg

Hello, first of all, sorry for my english, it is not my native language, With a lot of interest I pulled in all of your videos (several times): Im exactly looking for such program to get my IOT boards connected to a smart phone. Thanks a lot for this lessons and the time you spent. I followed your instruction to import the extension for BluetoothBLE. While connecting to my iphone13 with iOS 17.1.2 I received the message: Extensions are not currently supported by iOS devices. Do I something wrong here, is there a work around ?

hello sir, Can you make it for the wifi scan and connect to entered ssid and password and make user to control led?

Hi Mo,working using a BLE and wondering if you can assist me please. I just want to send AT commands over to the BLE without using arduino - serial over BLE.

Hi, I am using this tutorial and build a app to connect my ESP32 via BLE. When I click scan devices, it shows me a whole bunch of BLE devices. But if I use inbuild nrf connect app it only shows a very few BLE devices. Further, when I click on my ESP-32 server in the list, it doesn't connect to the device. Is there any particular reason? anyone can help please.

Thank you for a nice and very clear review. Unfortunately, it doesn't seem to work from Android version 12 and up. There will be problems with security and permissions. You can see but no connection takes place.

I am confused and I would like you to clarify if I send text or message from a cell phone to an esp32 so that the esp32 shows me on a screen who is the server and who is the client, clarify that I am confused to know that code to load the esp32 if the server or the client

Hello friend, im from Vietnam, I am participating in a contest and I have a question and need your help. I want to create a touch application on the phone, meaning that when the phone receives a signal from the BLE device, it will go to a layout or screen available on mitapp. Do you think this is possible?

Hello MoThunderz, do you plan to make an web app that uses web ble and do the same as in the android app, by the way, your videos are cool, I like them.

hi this video helped me a lot but I still have an issue: I would like to receive data from an esp32 even when the phone is off or when the app is in the background, do you have any advice for this?

hi siri is it possible if communication using ble takes data from esp32 real time

i am useing same library for esp32 but it showing name in NRF app in IOS but not showing in IOS Bluetooth setting place help me. i tried your code also but it not show name in ios Bluetooth setting.

Hi, Great video, what if i want to connect to my ESP32 auto ? without list and chosing the Bluetooth.

Great Video thanks. I followed very closely and everything works, except: When I move the slider I get the message on the phone "The variable $Slider_var is not bound in the current context". Also, no data shows up on the serial monitor. The data from the ESP32 shows up as expected on the phone app. I would appreciate any help!

Can you try to do this with actual android studio, the docs are terrible and the old videos do not work because the methods are depreciated

hiya, just such a great help .. im trying to achieve a specific task and have a lot to do, and having to write an app is the last thing i need to be doing lol .. so app inventor is going to speed things up a LOT .. however, you have kindly uploaded your bluetooth aia file for reference and i just CANT get it to upload - it says its not a correct file type .. i tried zipping it as well .. and using its url as a repository .. any ideas? .. just to save me a little bit of a mountain climb :)? kindest regards - steve

Hell, great video, would you no how to make it work for Ios? Says the Ios does not suport extensions. Thnakyou

is it possible to connect a esp32 ble to arduino nano 33 ble sense via ble?

I have a problem when trying to create more than 4 Characteristics. Using your BLE_Server code if I copy CHAR1_UUID renaming as _3, _4 etc the first 2 copies create Characteristics but more than that fails. So far after several days I am at a loss as to why. Grateful for any help. I did see a 5th Characteristic but that disappeared after I added the Descriptors and even without a 6th can't be created.

Doesn't work at all on my Samsung s22+. App just crashes out when you connect. Never did get it working

I would like to write the app in java with Android studio or something, can you provide some information on how to do this?

I can't able to see my esp32 on my list view😢is there any solution

Is it possible to show Android native app example other than MIT App Inventor. I got it working with MIT App Inventor but failed to make it working in native Android (Java) app. App is not connecting to ESP32.

I have a problem. I tried with de first block code when the app only show the devices list, but it never find any bluetooth device. I conced permission to use bluetooth and the precise location. Any idea? :c Note: using the tradicional BluetoothClient the app show the list of paired devices, but when i tried to connect with ESP32, the app shows me the error 507 like ESP32 was off

Hi , could you help, i am getting no serial output from the Arduino serial monitor .

can u show us in espressif ide pls

Hello friend, help, I get a permission not granted error. I am up to minute 12, in the first test of the app, and I get that it does not grant the Bluetooth permission

Hello Mo, I send and receive several variables to and from the ESP32 without any problems. But I also have variables that have to be sent by the ESP32 after the connection has been established and then sent back again after they have been changed in the app. I think this should work with one UUID. Do you have a solution for this? regards Joerg

Hello. Thank you for the tutorial. I can't get the app to ask for permission to scan o connect to bluetooth devices, when the app starts I get a message with error 908 saying that the permission has been denied and that I need to enable in the settings, but I can't do that either. I'm using a moto g51 with android 12. I also tried a beta version of the extension (20230223). Do you know any solution to this problem?

so this BLE extension can it work on the new Samsung phone? s22 and up???

How can i automatically pair a Device with Pin Code? I don't want to enter it every Time i start the App.

hello. please why happen this __ error 908: the per,ission BLUETOOTH_CONNECT has been denied. please enable it in the settings app

Yo estoy confundido y quisiera que usted me aclarara si yo mando texto o mensage desde un celular a un esp32 para que el esp32 me lo muestre en una pantalla quien es el servidor y quien es el cliente,aclareme eso estoy confundido para yo saber que codigo cargarle al esp32 si el de servidor o el de cliente

Waiting for a real tutorial with Android Studio

I am not able to search nearby bluetooth devices using this.Can u help me to get out from this difficulty.

Am getting an error stating " The companion has disconnected". May i know y ??

Why MIT Companion stops every time I change the Slider? Everything else works fine.

I am using Arduino nano and Bluetooth module HC-05. But it is not visible in the app.

I guess this is not working for iPhone, since extensions for bluetooth are needed.

Just keep getting this error "invoke: unable to invoke method `StartScanning` in object of type boolean. Irritants: () Note: You will not see another error reported for 5 seconds

It's not working on android 11 or greater

@33:35 Mobile App to ESP32

Can you help me apply this to the prototype i built based on this video? nRF Connect, 2020-11-05 TAIDOC TD1107 (C0:26:DA:01:D5:14) V 14:41:58.971 Connecting to C0:26:DA:01:D5:14... D 14:41:58.972 gatt = device.connectGatt(autoConnect = false, TRANSPORT_LE, preferred PHY = LE 1M) D 14:41:59.340 [Broadcast] Action received: android.bluetooth.device.action.ACL_CONNECTED D 14:41:59.385 [Callback] Connection state changed with status: 0 and new state: CONNECTED (2) I 14:41:59.385 Connected to C0:26:DA:01:D5:14 V 14:41:59.411 Discovering services... D 14:41:59.411 gatt.discoverServices() I 14:41:59.938 Connection parameters updated (interval: 7.5ms, latency: 0, timeout: 5000ms) D 14:42:00.230 [Callback] Services discovered with status: 0 I 14:42:00.230 Services discovered V 14:42:00.259 Generic Access (0x1800) - Device Name [R] (0x2A00) - Appearance [R] (0x2A01) - Peripheral Preferred Connection Parameters [R] (0x2A04) Generic Attribute (0x1801) Device Information (0x180A) - System ID [R] (0x2A23) - Model Number String [R] (0x2A24) - Serial Number String [R] (0x2A25) - Firmware Revision String [R] (0x2A26) - Hardware Revision String [R] (0x2A27) - Software Revision String [R] (0x2A28) - Manufacturer Name String [R] (0x2A29) - IEEE 11073-20601 Regulatory Certification Data List [R] (0x2A2A) - PnP ID [R] (0x2A50) Health Thermometer (0x1809) - Temperature Measurement [I] (0x2A1C) Client Characteristic Configuration (0x2902) Nordic LED Button Service (00001523-1212-efde-1523-785feabcd123) - Button [N W] (00001524-1212-efde-1523-785feabcd123) Client Characteristic Configuration (0x2902) D 14:42:00.259 gatt.setCharacteristicNotification(00002a1c-0000-1000-8000-00805f9b34fb, true) D 14:42:00.263 gatt.setCharacteristicNotification(00001524-1212-efde-1523-785feabcd123, true) I 14:42:00.321 Connection parameters updated (interval: 48.75ms, latency: 0, timeout: 5000ms) V 14:42:09.877 Enabling indications for 00002a1c-0000-1000-8000-00805f9b34fb D 14:42:09.878 gatt.setCharacteristicNotification(00002a1c-0000-1000-8000-00805f9b34fb, true) D 14:42:09.880 gatt.writeDescriptor(00002902-0000-1000-8000-00805f9b34fb, value=0x0200) I 14:42:09.976 Data written to descr. 00002902-0000-1000-8000-00805f9b34fb, value: (0x) 02-00 A 14:42:09.976 "Indications enabled" sent V 14:42:09.986 Indications enabled for 00002a1c-0000-1000-8000-00805f9b34fb I 14:42:10.074 Indication received from 00002a1c-0000-1000-8000-00805f9b34fb, value: (0x) 06-68-01-00-FF-DA-07-05-16-04-06-00-00 A 14:42:10.074 "36.00°C Time: 22 May 2010, 04:06:00 Type: Unknown" received V 14:42:11.178 Enabling indications for 00002a1c-0000-1000-8000-00805f9b34fb D 14:42:11.178 gatt.setCharacteristicNotification(00002a1c-0000-1000-8000-00805f9b34fb, true) D 14:42:11.180 gatt.writeDescriptor(00002902-0000-1000-8000-00805f9b34fb, value=0x0200) I 14:42:11.243 Data written to descr. 00002902-0000-1000-8000-00805f9b34fb, value: (0x) 02-00 A 14:42:11.243 "Indications enabled" sent V 14:42:11.247 Indications enabled for 00002a1c-0000-1000-8000-00805f9b34fb I 14:42:11.341 Indication received from 00002a1c-0000-1000-8000-00805f9b34fb, value: (0x) 06-68-01-00-FF-DA-07-05-16-04-06-00-00 A 14:42:11.341 "36.00°C Time: 22 May 2010, 04:06:00 Type: Unknown" received V 14:43:15.016 Reading all characteristics... V 14:43:15.016 Reading characteristic 00002a00-0000-1000-8000-00805f9b34fb D 14:43:15.016 gatt.readCharacteristic(00002a00-0000-1000-8000-00805f9b34fb) E 14:43:16.426 Error 133 (0x85): GATT ERROR V 14:43:16.490 Reading characteristic 00002a01-0000-1000-8000-00805f9b34fb D 14:43:16.490 gatt.readCharacteristic(00002a01-0000-1000-8000-00805f9b34fb) D 14:43:16.490 [Callback] Connection state changed with status: 8 and new state: DISCONNECTED (0) E 14:43:16.490 Error 8 (0x8): GATT CONN TIMEOUT I 14:43:16.490 Disconnected D 14:43:16.538 [Broadcast] Action received: android.bluetooth.device.action.ACL_DISCONNECTED D 15:43:04.916 gatt.close() D 15:43:04.975 wait(200)

hi there, thanks for the amazing work, after I scan the QR code on my phone, there's an error message on my laptop that says "Error from Companion: error: undefined variable. (irritants: yail/edu.mit.appinventor.ble.BluetoothLE)," could you possibly know how i can fix this issue please?

Hello Sir, Can I please contact you so you can help me with a small problem i have with receiving data, i am using Arduino Nano BLE 33 and MIT APP. Please, and if yes can I have your email.