Feature parity (having all features available on all platforms) is a goal with substantial priority. Since a few releases, they try to release new features or improvements on mobile and desktop simultaneously. Certain features are more useful to develop on Desktop first to make sure all bug and issue are resolved before developing for and releasing on mobile. (so you are correct, @Jeroen 
)
See also this topic as an attempt to list what you can expect on each platform. If you spot mistakes, let me know!