Hello, unfortunately, I also can't find the app on the store right now, on a new account.
It seems like they removed it currently, I investigated a little bit further on the case.

Their website is still up:

I contacted them via the eMail address given on that website, but I have to wait for their reply for now.

The only thing you could try is to download the .apk from a third party website like here and install it manually, but I haven't done so myself, this is at your own risk:

The app itself is still functional for me as of now, I just hopped on and tried it.

Sorry for the inconvenience, I'll post here in the comments again if I get a reply from the dev team.

Just used it with your referral. I got 4D. I installed apk from apk pure (at my own risk of course).

Posted using Partiko Android

Coin Marketplace

STEEM 0.26
TRX 0.10
JST 0.032
BTC 41764.03
ETH 2226.36
USDT 1.00
SBD 5.15