What do the different Collection tag versions correspond to?

We offer a property called Collection tag version that returns the version of the library from which the event was sent.

Based on the number, you can figure out from which library it was sent:

4.x.x > Xtcore
5.xx.x > Smarttag JS
6.xx.x > Piano Analytics JS SDK

2.x.x > Android or iOS Smarttag SDK
3.x.x > Piano Analytics mobile SDK