Updated as of June 2018 - Please read. When initially released, ReticleOS 4.1.14 (derived from Marshmallow, Android 6.0.1) had changes that were incompatible with Applications using Vuforia SDK for Digital Eyewear that worked fine on the R-7 when running previous KitKat based releases.
Vuforia completed an update to their SDK, version 6-5-23, that does support Apps running on the latest version of ReticleOS on R-7; note your R-7 ReticleOS will need to be updated to a later version that 4.1.14. You should be running 4.2.8 or later. If you don't know what version you have, go to System Settings -> About glasses -> System update and check for updates.
Once updated, you'll need the latest Vuforia SDK. Make sure to get a Version >= v6-5-23. (as of June 2018, the Vuforia SDK version is 7-1-34.
https://developer.vuforia.com/downloads/sdk (choose the Download for Android).
If you are using Unity, and have a recent version for Vuforia included, you need to patch your Unity environment. Note – 2017.2 Patch 2 was released mid November:
Finally, you'll need to rebuild your App with that new Vuforia SDK. Make sure to turn off multi-threaded rendering - see this this post on Vuforia's developer site.
If you are using Apps that are dependent on Vuforia built with an earlier version of their SDK, they will need to be recompiled; Ask your App vendor for an update.
You must also (re)calibrate your camera/display view. You must download the latest App to do this here: Calibration Assistant
You will need to print out this Calibration Target at 100% scale.
Sample App: Attached to this article is the standard TeaPot sample. It uses the standard Stones Target from Vuforia.
If you updated over the air to 4.1.14, or received new glasses recently that had 4.1.14 installed in the factory, and you want to run older Apps that use Vuforia tracking but those Apps have not yet updated to use the later Vuforia SDK, then you can downgrade the R-7 ReticleOS to 3.5.19 temporarily via this procedure. We are not recommending this now (June 2018) as most Apps have been updated, and this procedure may not work on the very latest hardware.
If you did downgrade, once the your Vuforia dependent Application has been updated to use the newer Vuforia SDK, it is simple to update again to a later version of ReticleOS via the standard OTA method.