No it's all done manual, if you do it you track it, if you don't, nothing gets tracked.

It also worth mentioning that you can track multiple activities simultaneously, but you just have to make sure that you push the buttons when you start and when they're done.

As I'm using an iPhone, it's helpful because I set Siri to respond to my voice command so I can start and stop the tracker using my voice it's very helpful for example if I start doing some push-ups I don't have to open up I just say which task to start and Siri will start it for me and then I tell her to stop.
The app works on Android as well but I'm not sure you can set such shortcuts.

If you want we can have a chat one of these days and we can speak more about tracking time.
Don't worry, I'm not trying to sell you anything, so if you want my help let me know.