I'm having problems with run-away memory usage whilst using ground plane in iOS. For a long time I thought it was my project, but I've now tried it on a blank project and the memory just keeps increasing.
This will continue until the device becomes unresponsive. Tested in Unity 2018.3.14, 2018.4.0, 2019.1.5 and vuforia 8.1.7 and 8.1.11. Occurs on iPhone 6, iPad Air 2 and iPad Pro. iOS 11 and iOS 12. Xcode 10.1.
If you stop and restart the positional device tracker it drops right back down then starts climbing again.
This is quite a rapid rise and can cause a device crash in about 30 seconds to a minute on lower memory devices. I'm pulling my hair out over this one as it is preventing us launching a client app.
This example project above consists of ARCamera, Plane Finder, Ground Plane Stage and a single primitive Cube.