The ability for us as recruiters/recruiting managers have complete access of our data in one place! This makes it easy when you are managing multiple accounts (iPad vs PC).
It's very user friendly so anyone who has any kind of experience using software will be able to pick up quickly without much training required since everything looks similar across platforms - making this helpful if not familiar. I haven't found anything about gem specifically but overall there isn't too many cons really either except maybe having different colors might look nicer than black white? However even just being consistent would help alot because they do tend towards looking like most other products out right now which could make them more marketable or at least less confusing compared to others currently available within its space.