Are you on the 1.2.1 version?
What do you exactly mean by "nothing happens"?
What does the status icon tell you when you tap on it (the cloud icon).
Which device are you on and what network connection do you have?
Yes, its updated. I'm on a iphone 5c. My internet connection is good. Optical fiber 60mb/3mb.
WHen I say nothing I mean nothing happens. lets say I add a photo... The cloud icon starts syncing and for 1 or 2 seconds i can see the three dots on it.. After that it stops and no photo... If i add let's say 10 photos, and of those 6 sync correctly, than the app while spend some time syncing those images but the remaining 4 will not sync. But they appear in the browser Lightroom as grey squares and if I try to open them, it says that its unrecognizable.
Could you send us a diagnostics log (enable it by going to the settings (Lr icon) and then once in the settings - pressing the Lr icon a couple of seconds.