You can use apktool to decompile the APK, then follow the Android build instructions in this repo's README to replace the library. Then rebuild the APK using apktool and sign it using apksigner before installing it to your Android device via adb.

Okay, so I learned how to decompile and recompile the APK, but the only instructions I see are for modifying the aar library. Here's the folder structure of the decompiled APK: http://imgur.com/a/w9uRI

How would I go about modifying it with your method from this point forward? Thanks for all the help so far.

The AAR file you need to modify (or replace with the one in this repo) should be inside the libs directory.

Okay, so here's the folder structure within the libs directory: http://imgur.com/a/w9uRI
The file doesn't seem to exist. Could it be hidden?

Ah I see. This is a compiled Unity project. Unity compiles multiple project libraries into shared object files. You might be able to decompile the shared object containing the AAR (assuming that it's still in that format), replace the AAR, and recompile. It would be simplest to modify the original Unity project, if you have access to it.

No, it was uploaded online so I don't have access. I also don't have Unity installed either. Is there possibly a way to modify the ARCore service APK provided by Google to support unsupported devices. Or can it only be currently accomplished on the actual app?

That's an interesting thought. It would make this modification far more universal. I'll look into it.

It's definitely something I've been contemplating lately. It could be like a hook service that runs on the phone so when you load up an APK using ARCore, it would spoof your device as compatible or disable the compatibility check. Although, something on this level might require root access. Thanks for all the help. I'm installing Unity now in hopes of using the method you mentioned above. I'll let you know how it goes.

Here's the link to the APK if you want to take a crack at it.
http://208107.selcdn.ru/TestVR_OPEN/TestVR_RC3.apk

Cool! Thank you. I built an early version of a modified ARCore Service, which seems to be functional without per-app modifications, all on my "unsupported" device.

Please try it on your device and let me know if it works. You'll need to uninstall the existing "Tango Core" first. Thanks!

Thank you, but the link appears to be down.

Sorry about that. I just updated the comment's URL.

No worries, I installed it but no luck yet. I'm gonna restart my phone and see if it works then.

Okay, so the unmodified HelloAR Java apk works without the modified aar file, but the other app I downloaded still displays the "unsupported" message. So far this is good as it seems the modified Tango Core apk does it's job for the most part. Hopefully Google will release new apps so we can determine if it only works with their apps or if it's dependant on which SDK the app is built under. Thanks again.

@NeoToriyama That's good to hear! Does it actually show a camera with full ARCore tracking? If so, which device are you using? Exciting!

Yes it does and the tracking works very well. I'm using the Samsung Galaxy S8+.

Thanks! Will close this once we complete testing and build instructions for the shared library.

Of course and no thank you for all the work. It's greatly appreciated!

Just confirmed that the tracking is much better on the unmodified Java APK. I don't know how it's possible, but after several tests back and forth I'm fairly certain. This could due to fact that it's a Java build. It also loads much faster than the modified HelloAR apk.

Good to know for testing the issue on other devices, thank you!

You're welcome!

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