E4 auto reconnect after some connection losses

[sboettcher]

With the newest E4 firmware version (3.1.0.7124), the device now sometimes goes into connection mode if it loses the Bluetooth connection, instead of simply turning off. It does not always do this, e.g. when it loses the connection due to being out of range, it still just shuts off.
I've not been able to reproduce this robustly, but have seen it happen from time to time in my personal tests. However, the app currently will not allow automatic reconnect of the E4 if the app is not active in the foreground and the screen is on.
We have now also gotten reports from several participants, saying that the device sometimes is still recording (PPG LEDs are still on), but not connected in the app anymore (after having previously connected it in the app and then not touched it again). This would also support the hypothesis, that the device sometimes loses connection for some (internal?) reason, then goes into connection mode, but cannot re-connect to the android device and switches to local recording after some time.

Is it possible to allow connections even when the app/phone is not active?
I know we had previously said this was not a priority since the E4 does not support it anyway, but since it now seems to at least try it sometimes maybe we can revisit this?

[afolarin]

• Do we have a confirmation that this is not the case for firmware versions prior to 3.1.0.7124
• for the participants with 80% data (I presume did not experience this), any ideas if they were on a different firmware

[sboettcher]

Do we have a confirmation that this is not the case for firmware versions prior to `3.1.0.7124`

To my knowledge there is no public changelog from Empatica about their newer FW versions >3.0, so unfortunately we don't know when this change happened. I can definitely confirm that this was not the case for versions <3.0.

for the participants with 80% data (I presume did not experience this), any ideas if they were on a different firmware

The version we used before the beginning of this year for Epi Study 1 devices was 2.1.0.4911. In Freiburg I only ever used devices with version 3.1.0.7124 for Study 2. I don't know which was used in London.

[afolarin]

@zulqarnain343 maybe has some insight into the versions in use in London.

[zulqarnain343]

On Empatica website they are still showing 2.1.0.4911, release Feb 2019 as latest. But when you connect new E4 to E4 Manager, it asks for firmware update. So I guess its 3.1.0.7124. Can be confirmed by connecting each device with E4 Manager.