New user here. Using Fire TV on 2 different television sets.
Was finding that the Preview app was slow.
So I installed the Tablo standard, aside from the Sync part. It is a lot faster and snappier.
Standard app is faster. Why is that? What is this sync?
Thanks
The preview app is similar to a beta release. It has a slightly different interface, and it does not need to sync upon startup. Some features start in the preview app and eventually make it onto the standard app. This app does not allow for remote streaming (assuming that is something you use - meaning if you want to watch your Tablo away from home, you cannot do so on the Tablo preview app). The preview app has a pop up guide so you can watch TV while looking at the guide. The standard app does not have this yet.
The standard Tablo app is the official release. The sync is your Tablo communicating with your streaming device (tv, firestick, roku, etc). Grabbing your recordings, schedules, etc. If you’ve set up remote streaming for watching your antenna away from home, this is the app you would use to do so.
I have found that even though I can scan for channels with the preview app, the standard app works better for this purpose. I prefer watching TV at home with the preview app to me it loads faster.
I don’t think I’ve missed anything, but if I did I’m sure someone will fill in what I’ve not mentioned. 
Happy streaming!
Oh, there is a thread here: NEW - Tablo Amazon Fire TV/Android TV App Update (v. 1.6.8)
and if you scroll down to the bottom @TabloTV has gone over a bit more about the differences between the 2 apps. I misspoke above about the purpose of the preview app, but this thread will help clear some things up.
Hope this information is helpful!
Thank you. Got it. I have since moved on to Nvidia Shield and the Preview version screams. Absolutely love it.