We strongly advise you to only use CanZE with dongles described below. 99% of the dongles on the well known auction sites are ELM327 clones and are build up from stolen and corrupt firmware. Using such a dongle may not work at best and put you and your car to unknown and unpredictable risks at worst

ELM327 dongles (KONNWEI 902)

ELM327 (clones) are cheap easy devices. Note however that the cheap no-brand ones from China can be useless for CanZE, as they lack certain essential commands. They often do not work, even if they work in your ICE car. More details here.


We know CanZE works with the Konnwei KW902. If you order on ebay.com.au you find the ones shipped from mainland China and Hong Kong. These are usually about half the price if you take shipping into consideration, compared to the ones shipped from Europe, but you will have to wait 3-6 weeks for it to arrive. The exterior of this device with the four screws and the LED’s and an off button on the top is very distinctive and easy to recognize. They come in different colors, but that is not relevant.

The Maxiscan KW902 and the OBDII 2 KW902 Scan Auto Scanner look the same, are probably identical inside and also work.

We had reports that the VGate 3 works too, but can’t confirm as we don’t have one.

Note that they are sold with Bluetooth or Wifi connectivity. The current Android application only supports Bluetooth, the iOS version only supports WiFi.

There is a dongle test app available for iOS here.

The following dongles are working on te iOS app:

  • KONNWEI KW902 (Wifi version)
  • LeLink BLE
  • VGate BLE

CanSee dongles

For real power users we developed an ESP32 based super fast CanSee dongle, tailored for use with CanZE. The project has it’s own page here.

It will set you back under EUR 20 in parts. Note that is an electronics build project. You need to build these devices yourself, and that includes soldering, hooking up a SAE J1962 connector, a transceiver, power converter, and mount it all in a proper case. We will absolutely not provide any help with that. But do expect several full screen updates per second, if your android device is up to snuff.

What should you choose?

The easiest choice are the ELM based dongles. They are insanely cheap (EUR 13 delivered and all if you are patient) and work out of the box. The downside is that they are slow. Especially for free frames, they need to be set up, then set to listen mode, then wait until that frame shows on the bus, then stopped. To check relatively static values, such as battery health, temperatures, charger performance, voltages, they are your choice. We have done a lot of optimizations to get as much as possible out of these devices. You can now expect a full screen update in the App about once per  second. Also there is an experimental feature called “Use ISOTP fields” that will avoid free frames all together.

If you want near real time performance of fast changing fields such as uncorrected speed, pedal positions, power and torque levels, you need the CanSee dongle. We let it monitor all free frames and store them in it’s generous memory, ready to be picked up by the app at any time. Downside is you need to build this device yourself.

Older DIY devices

In the (distant) past we have published code for Arduino Due and Teensy. The Due was relatively costly and is deprecated by Arduino. Both required extra Bluetooth hardware that the ESP32 boards have natively. Therefor these initiatives have been discontinued.

Future devices

We are working on implementing BLE support Android and intent to release that, including a recommendation for a slightly faster and BLE capable dongle. It’s an intent, not a promise. The iOS version already supports BLE.