The answer is No, yobit has no any mobile app but if you search in playstore you'll find yobit app which is not really they are scammer. If you installed it and try to log in your money will be stollen by hackers and you'll not have to blame yobit. Also in yobit domain, these are the really yobit domain
1: yobit.net
2: yobit.io
3:yobitex.net
These above are the only really yobit domains, if you inter your details to onother site a party from that your money will be stollen and yobit will not be relevant on that.
And the following are scam domain which are using yobit theme
1: Yobiti.com
2: yobittex.com
3: yobit mobile app
Don't use the mentioned website above you'll lose your money. Goodluck.