I've got several AR apps in development using older versions of Vuforia. I don't need either user-defined targets or cloud recognition for these apps, so I'm not sure if I should update.
Are there any performance improvements that were made to 2.0?
The release notes list a very vague feature, "Improved tracking robustness." What exactly is meant by that?
The 2.0 tracker is better able to maintain stable augmentations when there is relative movement of the target a/o camera. It's also less affected by occlusion and better able to exploit the features of the target. So generally your augmentations will be more stable under a broader range of conditions and use cases.
If recommend testing 2.0 w/ one of your existing apps to see whether these improvements will be beneficial. You'll want to review the migration guide for you SDK before you do though - https://developer.vuforia.com/search/apachesolr_search/migration
There are also numerous other improvements in areas such as the video playback samples, where a number of improvments has increased the robustness.
The other point to note is that the large volume of testing carried out is all with the latest SDK.
One final point to note is that 1.5.X is no longer available, nor supported - so if you are doing any development going forward, it is best to upgrade.
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