SDK 3.1.3 & 4.0.0 App Installation Process Broken

[Thomy13]

Hey,

Ever since the firmware update I am unable to build and install my app. I've tried SDK versions 3.1.x, 3.0.x and 4.0.0. Neither the web studio nor local build(s) would work.

The build process finishes correctly but the build basically gets stuck in an endless loop trying to launch the app:

Spoiler

No app package specified. Reloading ./build/app.fba.
Loaded appID:9d04c062-1377-45fb-9cb2-2d89c5c2782e buildID:0x037c101e109787ab
App install complete (partial)
Companion install complete (full)
Launching app
[1:45:11 PM] Companion: Loaded and evaluated: file:///android_asset/bootstrap.js (js-engine-bootstrap.html:9,1)
[1:45:11 PM] Companion: Loaded and evaluated: file:///data/user/0/com.fitbit.FitbitMobile/app_companions/9d04c062-1377-45fb-9cb2-2d89c5c2782e/0x037c101e109787ab/companion.js (js-engine-bootstrap.html:9,1)
[1:45:12 PM] Companion: Companion launched by [launchedOnTracker]
[1:45:31 PM] App: App Started
[1:45:15 PM] Companion: messaging: open (companion/index.js:84,13)
[1:45:15 PM] Companion: App closed on device, unloading companion in 3 seconds…
[1:45:34 PM] App: App Started
[1:45:15 PM] Companion: App was opened on device; companion will no longer be unloaded
[1:45:17 PM] Companion: messaging: open (companion/index.js:84,13)
[1:45:18 PM] Companion: App closed on device, unloading companion in 3 seconds…
[1:45:36 PM] App: App Started
[1:45:18 PM] Companion: App was opened on device; companion will no longer be unloaded
[1:45:20 PM] Companion: messaging: open (companion/index.js:84,13)
[1:45:21 PM] Companion: App closed on device, unloading companion in 3 seconds…

This then keeps going on forever until my watch reboots itself or until I force quit the process. I'd gladly provide more information if required.

All the best,

Thomy

[Thomy13]

I was able to find some more details regarding the issue. It seems that starting the heart rate sensor seems to crash the application and force a restart:

Spoiler

if (HeartRateSensor) {
    if (heartRateSensorModel)
        heartRateSensorModel.stop();
    let bpmText = document.getElementById("heartRate");
    heartRateSensorModel = new HeartRateSensor({frequency: 1});
    heartRateSensorModel.addEventListener("reading", () => {
        bpmText.text = heartRateSensorModel.heartRate || "--";
    });
    //heartRateSensorModel.start();
}

Executing heartRateSensorModel.start(); results in the app instantly crashing. Any ideas?

[Hibbem]

Same problem here. Some extra debug info:  `Cannot establish icomm session for this app. Try restarting.` 

Message disappears after disabling all the sensors