Sync has beaten the Boost app (also from Reddit but still in pre-register mode) )to go live on Lemmy. It is working perfectly well for me and has tons on customisation options around fonts, colours, spacing, layout choices, navigation options, etc.
It seems to have brought all those custom features across that made it so popular with Reddit users. Numerous comments are being made on Lemmy by ex-Reddit users saying they now feel fully at home. For them, Lemmy now has a completely familiar look and feel to what they were used to on Reddit.
I should just add though that some of the first Lemmy mobile apps are also present and there is really nothing wrong with them. They also have a good look and feel and it is well worth trying a few apps out to see which you like best. I currently have three apps installed, and I am registered on two Lemmy servers.
See https://play.google.com/store/apps/details?hl=en_US&id=io.syncapps.lemmy_sync