Why no Czech course on the mobile app?
Why is there no Czech course on the Duolingo mobile app?
contributors are not in on the technical secrets of how when and why something is or is not released. We, sadly, often learn from users that a function was enabled.
That said, I personally do not like the mobile version at all. It has so many bugs in English for Czechs that I fear the release of Czech for English. Even in languages that do not have that many issues the mobile course is easier to pass, by far, than the web based one. Which kind of beats the purpose. It is great if you are unable to get on regular web here and there and do not want to lose your day streak but I, personally, would strongly recommend not to rely on it.
Btw, cyrillic. Not sure what you are using as your operating system. Windows 10 comes with a "mnemonic" version of russian keyboard (install russian keyboard, change options to mnemonic). The layout is 99% identical with English keyboard and the extra characters like щ are created by combination of letters (s,c in this case). It allows one like myself to type all 10 in russian and my typing skill is now way better than my russian speaking skill. For previous version of windows such keyboards were downloadable from internet as an add-in or something like that.