I think google knows all about everybody. But actually, yes. Having “registration” sometime leads to uninstall the application without even try.
TimeTracker is an exceptional case for me. I tested It worked fine. And I switched from NowThenPro to TimeTracker. The killing feature is to enable to start timer even if phone is locked. Just swipe and start. NowThenPro could not do it (I need to login, click to start app… waste of time… and I could not accept such waste million time a day).
The reason to accept the “registration” requirement is the big pain (I need to unlock phone to start the timer)… I’m very lazy to allow extra click many time per day… It’s extremely annoying :-).
But this is the big exception. All other application have not took my attention… if i see registration form. Just uninstall very quick. Not because I care about privacy, but because I’m lazy and I need quick results (It’s ok to configure a lot of time, but during the usage use it very fast).
Maybe you are loosing a lot of users by this “registration requirement”.