Not widespread enough
This is great if you live in a major city that they have in their options, but unlike Google, those are the only options they have like London, Vancouver, Tokyo, etc. For those who live not far even from these cities it is useless. Until it is more widespread most people will have to stick with Google maps or Apple maps if they have availability with transit in their country already.
ActionGal_2010 about
Citymapper, v5.9.247