The platform have got its own application and it isn't available on the Play Store.
Am also wondering why the app is not available on the play/app store! I took the risk and downloaded the .
apk file directly from the website but am sure most users will be reluctant to do the same although scanning it with
virustotal says it's clean.
The website is well customized for mobile browsers. So, downloading the app is not really necessary.
They also have a Telegram bot but it's only in Russian language. It would be good if they make it available in other languages (mainly English).
^ I did not even try to download their application.
How much could the cost in validating your app in the Playstore?
I think this is the safest way if they are available in the Play store because we know Play store can detect those fake apps or have malicious apps to download. However, this could be the struggle of the OP, how can OP lure gamblers and the first step of download apk, much better if we browse it as a website.