Our client wanted to connect Garmin GPS device with an Android Device to transfer a file from mobile to GPS device using OTG cable. We created the app and delivered a build. He said the GPS device was not detected in our App but OTG Disk explorer could read it. We investigated the problem a little bit more and figured the problem was only occurring on his Nexus device. We reverse engineered the OTG disk explorer App to see how the OTG disk explorer was reading memory and figured that it was using low level disk reading algorithms to read the internal memory.
Developing low level disc reading algorithm for this small task and in limited time was not a feasible solution. We just removed the SD card from device and try connecting it to Android Device. The Android Device connected the internal memory in this attempt. But again, not a feasible solution to pull the SD card out to transfer file to internal memory from Android Device. Eventually we told our Client that we could not solve this problem in the way he envisioned it.
Now he is working on a custom device that can connect the Mobile devices via Bluetooth and interfaced with GPS device via USB. He will probably use Raspberry Pi for portability. He will get back to us for further development once he is done with this custom device.
- OTG Storage doesn’t work with Google Nexus devices.
- Android discourages use of external storage. This usage will be prohibited on Android OS 4.3 and above. Google just wants developers to use the Cloud storage.
- Android Kit Kat versions don’t have a facility to mount any external storage device via USB/OTG.