30th July Update has cause Bluetooth to stopworking!

I have an app that connects to BLE devices (ESP32 based).

Everything has been progressing smoothly until today when I updated to the latest Companion and presumably an updated online MIT App Inventor.

My phone is able to detect the BLE devices but the App does not!

I have gone back to previously saved versions of the App and they don't work either.

I have also restarted my phone several times with no luck.

I have been developing this project for over 6 months and have only had a few minor Bluetooth problems and none for a few months.

I am using this bluetooth extension edu.mit.appinventor.ble-20190701.aix

Is there anyway of going back to an earlier version of MIT App Inventor?


Ian James

BLE extension 20190701 Date Built 2020-04-07 works for me in nb184. Companion 2.59. Arduino UNO + HM-10 (BLE module).

What version of Android are you running on your device? If you're on Android 10, the app now needs fine location permissions due to a policy change in Android. You should be able to use this experimental version of the BLE extension on Android 10:

Hi thanks for the update.

Unfortunately it has had no effect, my app still does detect any BLE devices when scanning i.e. through the BluetoothLE1.Found event.

Previously all sorts of BLE devices were detected i.e. Ionic watch, Headphones etc. which I filtered out in order to connect to one of my many ESP32 BLE devices.

Now I get no Found events at all.

I have gone back to saved versions to no effect, although these are not compiled apks just old versions loaded into the Inventor and the build again.

I have even written a minimal app to search discovers these devices and that does not work either.

My phone is a HUAWEI Mate 20 Pro LYA-L09 android version 10

I have been using it with MIT App Inventor for the past 8 months with no problems and it hasn't performed an update for a few weeks now.


I stated that on Saturday 1st August I had ensured I was using the latest BluetoothLE extension 2019070 and had noticed no improvement.

I tried the live method and downloaded a built apk both resulting in no detection of BLE devices of which there are many.

Come Monday morning I logged in and tried both methods again and lo and behold everything is now working despite nothing apparently changing!

Everything is back working as it was on Friday morning which is obviously good news, I am just left wondering what has changed between Saturday 1st August pm and Monday 3rd August am.


Ian James