No apps allow mobile syncing right now, but I'm hopeful that will be resolved once 8.1 is officially released
I use
fitbit tracker
It's well organized, simplistic, and provides sufficient information at a glance
I've never tried it because fitbit companion has been sufficient, but I've read good things about
Fitbit Companion
Health State is another app that can access fitbit data and it has a different layout and style from the previous two apps