according to steam 10% of our players have played for >10H
According to unity analytics its 1% (Using Custom Audience Total Time played Ms > 36,000,000)
Total_Time_PlayesMs appears to be in ms ie using a million gives me what I would expect nearly all users because thats like 20 minutes…
I often found that my personal steam play time for some games does not match my perception, especially those under an hour. My guess is that steam starts counting the moment you click on that play button, and only stops when the play (now: stop) button reverts to play. This means any time spent initializing and loading the game may be added to total play time.
It‘s in Steam‘s interest to report the highest possible play time.
Building on the previous reply.
The msSinceLast event parameter is injected into each analytics event as it is processed on the server. It is the delta in milliseconds since the previous event. A sum of this value, grouped by sessionID can help you understand session lengths. The Total_Time_PlayedMs is a SUM of this over all time for a player.
Going back to your question about the differences between Steam and Unity session length reporting. Keep in mind that analytics will respect backgrounding behaviour. It will stop sending events whilst in the background and will generate a new session if backgrounded for more than 5 minutes. Also, keep in mind that backgrounding behaviour can be configured in Player Settings and can vary depending on the platform you are on.