It's been my good experience to attach with this app and I personally feel this is a legal app and we get much more from this app.
In this u have to first register ur bank with this app and set ur own upi pin which u have to remember at urself. This app doesn't ask u for any investment and gives u a lot. If u share your link to anyone then u will be rewarded with Rs50 and there is also many more contests where u can earn a scratch card and may be u could win money having their limit range.
Whatever money u get, will transfer into your bank account.
So I think this is an amazing app and everyone should love this.
