Never heard about this mobile wallet, I've checked the website and those images are interesting and encouraging to use this wallet. There are integrated DAPPS on this wallet.
But this doesn't mean that I'm already convinced of trying it and will deposit amount, no. @OP is there are way to know on how many current users they have? this can validate that the community trust this wallet.
Try to check it on
https://www.appannie.com/en/ . Try to read other articles in their website about HB Wallet. It's the top wallet in Japan.