> ## Documentation Index
> Fetch the complete documentation index at: https://docs.naubat.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Compatible Dongles
> What kind of OBD dongles work with Naubat, and which ones are the best fit
# Compatible Dongles
Naubat works with Bluetooth Low Energy, BLE, OBD-II dongles. It does not work with Classic Bluetooth adapters.
This is the first requirement and the most important one. If a dongle is not BLE, the Naubat app is not compatible with it.
## Minimum Compatibility Requirements
A dongle is generally compatible with Naubat if all of the following are true:
* It uses BLE, not Classic Bluetooth.
* It behaves as a standard open OBD dongle and is not locked to a single app or product ecosystem.
* It supports the ELM327 command model, or an equivalent implementation compatible with it.
* It allows the app to exchange diagnostic messages reliably with the vehicle.
Most consumer OBD dongles on the market are based on the ELM327 family, or on chipsets and firmware derived from that communication model.
That includes simpler and more advanced implementations.
Naubat is designed to work with this broad ELM327-compatible category.
Some dongles may appear to match the right hardware profile but are intentionally locked to a specific product, app, or vendor ecosystem. In those cases, Naubat is not compatible with them.
In practice, Naubat is compatible with open or "free" BLE dongles that expose standard diagnostic communication to third-party apps.
## Compatible Does Not Always Mean Ideal
Compatibility means the app can connect to the dongle and exchange messages with it, and the dongle can translate those messages into a format the vehicle understands.
That is only the starting point.
Among compatible dongles, some are clearly better suited to Naubat than others.
The most suitable models behave more predictably in daily use and reduce edge cases around sleep state, reconnection, and vehicle activity detection.
## Brands Commonly Seen
The two families we most often highlight are:
* **Vgate**
* **Veepeak**
Both brands include models that can work well with Naubat, although behavior still depends on the specific model and firmware implementation.
## What Makes a Dongle Better for Naubat
When comparing compatible dongles, we mainly look at three things:
1. Throughput and responsiveness
2. Auto-sleep and auto-wakeup behavior
3. Voltage reading accuracy
### 1. Throughput and Responsiveness
A higher-performance dongle can move more bytes per second and usually handles request sequencing more cleanly.
That is generally preferable.
At the same time, this is not the most critical factor for Naubat.
Naubat does not rely on aggressive high-rate polling.
In normal operation, the app usually sends only a small number of diagnostic requests, commonly around two messages per second.
In theory, almost any decent commercial dongle should be able to handle that load.
In practice, real behavior depends on firmware quality, internal buffering, and how well the dongle handles rapid command sequencing.
If you want to compare raw throughput across models, a good external reference is [Sidecar's scanning guide](https://sidecar.clutch.engineering/scanning/).
It is well documented and provides a useful comparison of scanner behavior, including throughput figures for many commonly available adapters.
We still treat throughput as only one part of the decision, not the only decision criterion.
### 2. Auto-Sleep and Auto-Wakeup Behavior
For Naubat, the ideal dongle behaves like this:
* When the vehicle is turned off, the dongle enters sleep mode.
* While sleeping, it is no longer reachable over Bluetooth.
* When the vehicle becomes active again, the dongle wakes up and becomes available for the app to reconnect.
This is the cleanest behavior because it matches the way users expect the app to behave around parked and active vehicles.
Many dongles do not behave like this by default.
One model that generally does, and that also satisfies the other important requirements, is the **[vLinker FD+](https://amzn.to/4lroBvZ)**.
For that reason, it is currently our main recommendation.
Good auto-sleep and auto-wakeup behavior improves the everyday experience more than raw throughput does.
Some compatible commercial dongles expose programmable parameters that let you modify sleep behavior.
This is commonly done through ELM327 programmable parameters, often called `PP`.
Even after configuring sleep behavior, real-world behavior must still be verified.
Some dongles enter a low-power state but remain visible over Bluetooth and wake up again as soon as the phone reconnects to them.
That is not the same as becoming truly unavailable while the vehicle is off.
#### What this means in real use
* If the dongle does not fully disappear when the vehicle is off, the app may still connect when you are nearby.
* This does **not** mean Naubat will start polling the vehicle continuously while it is parked.
* Naubat has an additional safety layer and only starts extracting data when vehicle activity conditions are met.
* In that scenario, the app may show a connected state even though no meaningful vehicle polling is taking place.
This can still be slightly annoying if the vehicle is parked very close to home, especially in detached houses or garages within BLE range.
If that becomes inconvenient, the simple workaround is to unplug the dongle or close the app when needed.
### 3. Voltage Reading Accuracy
Naubat continuously checks the dongle supply voltage using the standard ELM327 command `AT RV`.
This value is used as one of the inputs for deciding whether the app should remain in `Idle` or move into `Collecting Data`.
Ideally, the dongle reports a voltage very close to the actual 12 V battery line of the vehicle.
Some dongles do this well.
Others systematically report a lower value, often around 1 V below the real battery voltage.
Examples reported by our tests and field experience:
| Model | Voltage behavior |
| -------------------------------------- | --------------------------------------------------- |
| Veepeak BLE | Often reports around 1 V below real battery voltage |
| Veepeak BLE+ | Often reports around 1 V below real battery voltage |
| Vgate iCar Pro 4.0 | Often reports around 1 V below real battery voltage |
| Vgate iCar Pro 2S | Usually close to real battery voltage |
| [vLinker FD+](https://amzn.to/4lroBvZ) | Usually close to real battery voltage |
Differences of around 1 V are usually manageable in practice.
Larger deviations can affect Naubat logic and can also indicate a dongle calibration issue that may influence other behavior.
## Our Practical Recommendation
If you want the simplest and most predictable experience, choose a BLE dongle that is:
* Open to third-party apps
* ELM327-compatible
* Stable under repeated command sequencing
* Able to sleep when the vehicle is off
* Able to wake when the vehicle becomes active again
* Reasonably accurate when reporting supply voltage
Today, our preferred recommendation is **[vLinker FD+](https://amzn.to/4lroBvZ)**.
Other BLE dongles from **Vgate** and **Veepeak** can also be compatible, but some models may require more compromise around sleep behavior or voltage calibration.
## Advanced Configuration and Validation
The sections below are optional.
They are intended for users who want to inspect or tune dongle behavior more deeply.
Compatible dongles in this category expose programmable parameters.
Use the `AT PPS` command to inspect them.
```text theme={null}
> AT PPS
00:FF F 01:FF F 02:FF F 03:32 F
04:01 F 05:FF F 06:F1 F 07:09 F
08:FF F 09:00 F 0A:0A F 0B:FF F
0C:68 F 0D:0D F 0E:7A N 0F:D5 F
10:0D F 11:00 F 12:FF F 13:55 F
14:50 F 15:0A F 16:FF F 17:92 F
18:31 F 19:4F F 1A:0A F 1B:0A F
1C:03 F 1D:0F F 1E:4A F 1F:FF F
20:5D F 21:FF F 22:FF F 23:FF F
24:00 F 25:00 F 26:00 F 27:FF F
28:FF F 29:FF F 2A:3C F 2B:02 F
2C:01 N 2D:01 N 2E:80 F 2F:0A F
```
Programmable parameter `PP 0E` controls auto-sleep behavior.
For the compatible dongles we know, this is the relevant parameter for:
* Whether auto-sleep is enabled
* How long inactivity must last before sleep
* Whether low-power behavior is allowed
Two common values are:
| Value | Typical meaning |
| ----- | -------------------------------------------- |
| `FA` | Auto-sleep enabled, longer timeout behavior |
| `A2` | Auto-sleep enabled, shorter timeout behavior |
The exact bit-level interpretation depends on the firmware implementation, but this is the parameter that governs the sleep profile.
A common configuration pattern is:
```text theme={null}
> ATPP0ESVXX
OK
```
Replace `XX` with the desired value, for example `FA` or `A2`.
After changing the value, validate real behavior instead of assuming the change is fully applied:
* Turn the vehicle off
* Wait for the expected timeout
* Check whether the dongle truly disappears from BLE discovery
* Turn the vehicle on again and verify that it becomes reachable
To inspect reported supply voltage:
```text theme={null}
> AT RV
12.4V
```
Compare this with a direct battery measurement using a multimeter.
If both values are close, the dongle is usually a better fit for Naubat's idle-versus-active detection logic.
If the dongle reports a clearly incorrect voltage, you can sometimes correct it with voltage calibration.
Recommended procedure:
1. Measure the real 12 V battery voltage with a multimeter.
2. Read the dongle voltage using `AT RV`.
3. If the difference is significant, use a serial terminal app that can send raw ELM327 commands.
4. Send `AT CV dddd`, where `dddd` represents the calibration target in `dd.dd` volts.
Example:
```text theme={null}
> AT CV 1260
OK
```
A practical tool for this kind of testing is **Serial Bluetooth Terminal**, or any equivalent app that allows manual command entry.
Small voltage differences are usually acceptable. Larger errors can affect Naubat state detection and may also point to inconsistent dongle behavior more broadly.
## Scope of Compatibility
Naubat cannot guarantee compatibility for every BLE dongle on the market.
Even within the ELM327-compatible category, implementation quality varies significantly.
Our working position is:
* Open BLE dongles based on the ELM327 model are generally compatible
* Some models are better suited than others
* Sleep behavior and voltage reporting matter more than marketing claims
* Verified models remain the safest choice when reliability matters