"Tips and notes" in the mobile version?
So far I'm mostly using the mobile app (Android). I completed the Italian course and just now saw that there are useful "tips and notes" for most lessons on the duolingo website. It would be great to have the same in the mobile version as well as I'm frequently using duolingo when I'm not at home.
Also I just started the Czech course which is "beta" and not accessible from the mobile app, what is the reason for this?
Have a look at a similar question in this thread, and the answers of the CEO of Duolingo
Workaround for App users
The grammar "Tips and notes" are available in the desktop mode of the browser of your phone/tablet.
In the Firefox browser you can select the "Desktop mode" via the three dots in the upper right corner of the screen.
(Note: This may be not working on iOS phones with a small screen)
I agree with you that we need tips and notes in the mobile app as well.
As for Czech, it is probably too new and the app has not yet been update to accommodate that language. For example I would like to use the Windows app to practice Kiswahili, but it is too old and the language is too new (still in beta). Fortunately the Android app lets me practice Kiswahili.
I didn't even know there was a Windows app as well! Anyway it's a great thing that Duolingo is offered across so many platforms and it would be lovely if each offered the same selection of languages. Currently I can use my mobile to refine my Italian and learn a bit of Spanish, for Czech I have to go to the website.