Cool. Thanks for sharing the solution here @devsleeper !

@panagiotis-milios Thank you for your response, appreciate your time ! I solved the issue : The url I was using was wrong, more precisely I was using the wrong servlet : I was using /dispatcherv2 while I was supposed to use /s2sdispatcher. I also want to point out that you are right about the "appId" below the "packetId", it is not needed. Thank you, I hope this thread will help anyone encountering this problem !

Hmm, not really... You can get the number of sessions created in an hour with this call: https://getbraincloud.com/apidocs/apiref/#capi-globalapp-sysgetdailycounts But brainCloud doesn't otherwise track a concurrent session count per app. There are certainly 3rd party analytics packages that you could link into your client that would give you that sort of information though. Paul.