AprilTags discord: https://discord.gg/g2ctkXB4bb
owoTrack on the play store: https://play.google.com/store/apps/de…
for ios you need to join testflight from their discord
If you have a Kinect (or PSmove), check out Kinect2VR https://k2vr.tech/
Check out SlimeVR, pretty cool stuff, you can use your own hardware too https://docs.slimevr.dev/
If for some reason you have 5 spare phones you can set the all up as trackers.