Digital gold investment, jar and gullak real or fake?

Hello everyone I'm new in investing, exploring on my own. I wanted to know thoughts on daily digital gold investment of ₹10-20 through apps like jar and gullak.

I have 3 questions

1. Is digital gold investment a good option and worth it?
2. Are jar and gullak genuine ? (give easy investment plus withdrawal)
3. If they are genuine, which one would you prefer?