Initial feedback and a few questions

[patrikdj]

Hello Evothings team,

I had the opportunity to be one of the early testers of Evothings Studio, and first I would like to say that my overall conclusion is that your development tools are very impressive. Also I am confident that my view should soon be confirmed by many other beta testers, Evothings Studio will be considered very helpful once released I am sure.

Given my background in R&D of mobile phone devices, and also lately in BLE embedded applications (i.e. BLE accessories), I was mainly looking into the Evothings example applications related to Bluetooth Low Energy. The examples are useful indeed, and it seems application development should be easy based on the examples you provide already now. In order to provide a bit of constructive feedback at this point I can say that during my experiments with the TI sensortag I noticed some stability issues . What I noticed was that sometimes (not always, should be easy to reproduce though) the BLE connection establishment procedure, after discovery phase when the TI sensortag is advertising was not successful in combination with a LG Nexus 5 Android 4.4.2 device. I did not had chance to analyze exactly why yet, nor did I had the opportunity to reproduce this with another Android device, perhaps you may want to look into this issue by doing some tests on your side. If you want I can send a log file.

When looking into your documentation I read that ”Mobile devices must be on the same local WiFi network as the computer running EvoThings Workbench to be able connect using the Scan" method”. My setup was using a Macbook air running Evothings workbench and a LG Nexus 5, both connected to same WiFi network.
Now, I did not test myself, but I assume it should work fine also if a PC/Mac would be connected using ethernet cable to same LAN, right?

Another more general question that immediately came to my mind was when do you plan to support the Evothings mobile app also for iOS7? I assume you are busy working on that now, and chose to focus on Android for a start, anyway I am looking forward to the Evothings mobile app for both Android and iOS eventually.

Thanks a lot Evothings team!

[micke]

Hello Patrik!

Thanks a lot for sharing and for your kind words!

Ethernet cable should work fine! The important thing is to be on the same network, so the machine is reachable via UDP broadcast.

BLE on Android has some issues, and I am still learning about limitations and workarounds. Did you have a chance to try the BLE Scan example? It is written to be as stable as possible, and while it does not connect to any device, it serves as a test of basic device scan functionality. I had it working stable on both Nexus 5 and Nexus 7. Interestingly however, Nexus 5 continuously reports devices as fund, while Nexus 7 reports them just once per call to startScan. I found iOS has a behaviour similar to Nexus 7. However, on iOS, a device like StickNFind is reported many times per scan, and I think this is because it advertises itself using different names each time (but same id).

Regarding iOS, I am working on an EvoThings client app for iPhone/iPad. Just committed some code I have been working on today, for the Cordova BLE-plugin on iOS: https://github.com/divineprog/cordova-ble

Thanks again!

Regards, Micke

[patrikdj]

Hello Micke!

Thanks a lot. I have tried out the BLE scan example before, and today I did a few additional tests here using my LG Nexus 5 Android 4.4.2 device.

I used a TI sensortag (upgraded with FW 1.4.0) and also two sticknfind out of the box The BLE scan example find them all, and present the TI sensortag
with the name ”SensorTag” while the two sticknfind BLE devices are reported with strange names (letter followed by two digits) that changes after stop/start scanning in BLE example app. Then I used an iphone4s and launched the app by sticknfind, and then the two sticknfind devices becomes connected. A new scan using the BLE scan example app now only finds the Sensortag, which is expected since the two stick find devices stops advertising when connected. After killing the sticknfind app on the iphone, the two sticknfind devices starts advertising again, and can be found by BLE scan example app again.

So, my impression is that the BLE scanning itself seems working fine, while the strange naming of the sticknfind devices imply some issue with handling of the device names?

BTW, would it be possible to add some kind of GUI notification when Evothings mobile app starts to check/allow user to enable WiFi and Bluetooth? I always seems to forget that I disabled WiFi on my smartphone to save battery life …

Thanks in advance.

BR, Patrik

[micke]

Hi!

Yes, I have also seen StickNFind advertising itself with different names (but the same address). I don't know why this is the case, I need to read up on the StickNFind documentation.

Support for turning WiFi on from the app could be implemented as a Cordova plugin, or natively in the EvoThings app (but then it would not be available to other apps). I think it is possible to turn on WiFi from an app on Android (at least I have done this with Bluetooth), but I don't know if it can be done on iOS and Windows Phone.

Best, Micke

[patrikdj]

Hello Micke,

I read somewhere that some BLE devices may chose to use private addresses (randomly generated addresses) instead of fixed addresses.
So I suspect that StickNfind may have implemented such private address, where such address then would be used during advertising …
Not sure, but I think that this private address would change into another address after a BLE connection is ended, i.e. if stickNfind goes back into
advertising after disconnection it may use another random (private) address.

Do you know how BLE scanning is implemented on your side, i.e. if passive scanning or active scanning is used (and what are the parameters used for scan type, scan interval, scan window, scan filter policy)?

Cheers,

Patrik

[Fredrik]

Do you know how BLE scanning is implemented on your side, i.e. if passive scanning or active scanning is used (and what are the parameters used for scan type, scan interval, scan window, scan filter policy)?

We use Android and iOS APIs. Android doesn't let you choose any scan parameters. iOS lets you choose only two, and I'm not sure how they map to the ones you mentioned.

We follow the Android style, using whatever default parameters the platform supplies.

[micke]

Related discussion: viewtopic.php?f=8&t=1816