What is Device Reachability?
Device Reachability is an API that returns the following three pieces of information:
- Is the device on a mobile network? (tru.ID’s SDKs can help you force the connection for the request to be over a cellular data connection if available)
- Does tru.ID have support for this mobile network operator?
- Which products (PhoneCheck, SubscriberCheck, SIMCheck) does tru.ID have for this mobile network operator?

When should I use this?
The three status checks listed above (PhoneCheck, SubscriberCheck, and SIMCheck) won't charge you unless they reach the `COMPLETED` status. However, the user experience could be impacted unless a Device Reachability check is first made.
Two possible reasons to use a Device Reachability check are:
- You have a mobile web application, which requires the use of a web browser. There is no way to force a cellular data connection on a web browser. So it’s important to first check the connection is cellular, and then check that tru.ID supports the user's mobile network operator.
- Your mobile application may require the knowledge of whether tru.ID supports the MNO in order to present a specific UX. (For example, if you carry out a Device Reachability check and the MNO is supported, you simply need to show a loading indicator while the tru.ID check is performed silently. Whereas if the MNO is not supported, you might show an SMS OTP generator as your fallback method of verification.)
The tru.ID mobile application SDKs (Android, iOS, React Native, and Flutter) have native functionality to force a cellular data connection with the function `openWithDataCellular`. In case of failure, you could display a different UX / authentication flow. Because forcing a cellular data connection is not possible in the web browser, the Device Reachability check could output a request to turn off WiFi before proceeding.
The technical side: How do I use this?
To create a Reachability check, you’ll first need an access token:
If the device has a mobile IP address and the mobile network operator supports tru.ID, a successful response will show the network details and supported products (PhoneCheck, SubscriberCheck, SIMCheck).
A response may look like this:
Conclusion
We hope this blog post has helped introduce you to tru.ID’s Device Reachability, how it works, and when you would need to use it when implementing tru.ID’s Checks in your authentication flows.
You can find more technical information regarding Device Reachability on the Developer Documentation page and the API specifications.
If you have any questions, feel free to contact help@tru.id, get involved in our dedicated Slack group, or get in touch with Sales.