OBD-II Device Performance (with Test Results)

[Weston@HPTuners]

We're often asked, "What's the best OBD-II device for TrackAddict?"

The OBD-II sampling rate you'll get in TrackAddict will depend on your OBD-II device, your vehicle, which data channels you have selected (and how many), wireless signal conditions, your Android or iOS device (and any other tasks running on it), and so on. There are a lot of variables! The reliability, consistency, number of available data channels, and other capabilities will also vary depending on these variables.

In an attempt to put some numbers to this, I'm sharing some observed sample rates using my already-existing collection of several OBD-II interfaces, smartphones, and ECU's / vehicles. As you'll see, the ranking order can change a little depending on the situation...

Before we get started, there are some inexpensive "ELM327" clone type devices included here, marked with an asterisk *. Although some are better than others, this general category of device has been very problematic for us and other apps, and is not recommended or officially supported. I'm using this as an opportunity to show why.

(Note that these are simple observations in a non-controlled environment, attempting to see how TrackAddict (v3.3.3) performs with certain devices in a few specific configurations. It's not a be-all or end-all test. There are many variables, and possible outside factors, so your own performance and repeatability may vary.)


Median Results for ECUsim 5100 (default configuration, 11-bit CAN @ 500 kbps, sampling 3 data channels)
1) OBDLink MX Bluetooth: 8.25 Hz (Android Only)
1) OBDLink LX Bluetooth: 8.25 Hz (Android Only)
3) PLX Kiwi Wifi (version 1): 7.40 Hz (iOS Only, See Notes)
4) *BAFX Products - Bluetooth: 6.20 Hz (Android Only, See Notes)
5) GoPoint BT1A Bluetooth: 5.20 Hz (iOS Only)
6) *Vgate - Bluetooth: 4.80 Hz (Android Only; Problematic, See Notes)
7) PLX Kiwi Bluetooth (version 1): 4.60 Hz (Android Only)
8) *Clone "ELM327" / CLK Devices - WiFi: 2.30 Hz (Android & iOS, See Notes)

Median Results for 2006 Chevrolet Trailblazer (LS 4x4 automatic, VPW, sampling 3 data channels)
1) OBDLink MX Bluetooth: 3.55 Hz (Android Only)
1) OBDLink LX Bluetooth: 3.55 Hz (Android Only)
3) GoPoint BT1A Bluetooth: 3.30 Hz (iOS Only)
4) PLX Kiwi Wifi (version 1): 3.20 Hz (iOS Only, See Notes)
5) *BAFX Products - Bluetooth: 3.05 Hz (Android Only, See Notes)
6) PLX Kiwi Bluetooth (version 1): 2.55 Hz (Android Only)
7) *Clone "ELM327" / CLK Devices - WiFi: 1.50 Hz (Android & iOS, See Notes)
X) *Vgate - Bluetooth: Failed to Connect (Android Only; Problematic, See Notes)

Median Results for 2014 Chevrolet Corvette (Z51 2LT manual, 11-bit CAN @ 500 kbps, sampling 3 data channels)
1) OBDLink MX Bluetooth: 6.10 Hz (Android Only)
2) GoPoint BT1A Bluetooth: 5.80 Hz (iOS Only)
3) *BAFX Products - Bluetooth: 5.05 Hz (Android Only, See Notes)
4) *Vgate - Bluetooth: 3.85 Hz (Android Only; Problematic, See Notes)
5) PLX Kiwi Bluetooth (version 1): 3.80 Hz (Android Only)


Android Bluetooth Performance: ECUsim / Trailblazer / Corvette (using OBDLink MX Bluetooth)
Samsung Galaxy S3 (Android 4.4.2): 8.7 / 3.8 / 6.7 Hz
Samsung Galaxy S5 (Android 5.0): 7.8 / 3.7 / 6.3 Hz
Google / LG Nexus 5 (Android 6.0.1): 9.7 / 3.4 / 5.9 Hz
LG G5 (Android 6.0.1): 2.2 / 2.1 / 4.5 Hz (See LG Notes below)

LG Devices with Android 6.0: There may be reduced Bluetooth performance with the LG G4, G5, and possibly others on LG's early versions of Android 6. It would seem to be related to this OS version, as it has been reported that the G4 had higher BT OBD performance on Android 5.
Update: The July 26, 2016 update for the LG G5, and other subsequent software updates, appears to greatly improve Bluetooth performance to a level similar to that of other Android devices. As such, the LG G5 test results reported here are likely no longer applicable for many users.

Android 6 in general: The OBD Live Monitor screen (and therefore these tests) can report a lower sampling rate than what you'll actually get when recording a session. It looks like Android 6 is automatically reducing the CPU speed when the device isn't needing to do much processing, in an attempt to maximize battery life. If you increase the CPU workload, or even just tap on an empty area of the screen, the performance goes up a bit. This impact on our performance would appear to be new with Android 6, and I have observed this behavior on Android 6.0.1 with both a Nexus 5 and an LG G5. It had a more noticeable impact on the LG G5, which has lower Bluetooth performance in general (maybe an issue in LG's Android 6.0). This behavior does not fit the Android "Doze" or "App Standby" features as they are currently documented, and using the Settings app to turn off Battery Optimization for TrackAddict did not improve this situation. The good news is that it isn't so much of an issue when actually recording a session, because we're doing more work at that time, so Android is giving us a higher CPU speed there, which then increases the OBD sampling rate.


Test Notes
* Very inexpensive "ELM327" clones are a frequent source of OBD problems and complaints, and are therefore not recommended or officially supported.
Vgate appeared to have intermittent problems reporting VIN info via OBD-II Mode 09, and failed to function on the Trailblazer.
The BAFX device is categorized as a clone here, but it did test reasonably well for me and appears to have good reviews, so it's borderline.

OBDLink LX and MX were the only devices tested that offered secure pairing (BT versions requiring a button press, WiFi version uses a password)
OBDLink MX is also available as a WiFi version (supporting both iOS and Android), however the early-production unit I have was not suitable for testing

PLX Kiwi Wifi (version 1) showed intermittent drops in speed, and was not visible to Android devices (its Bluetooth version worked well for Android)
PLX Kiwi Versions 2 and 2+ should also work and may have different results. Based on talking to users, Version 2 does seem to be better than 1.

GoPoint BT1A is Android-compatible, however TrackAddict currently only supports its unique protocol on iOS


Full data in attached spreadsheet image:
OBD Performance Test - 20160502.png