I'm starting a project and I'm looking for a company that offers an e-wallet service where I can create multi-user so they can transfer crypto-currency balance from one to another.

I found the https://rahakott.io that offers exactly the service I need, including APIs to integrate with my website. However, I would like to know other similar websites.

Important details:
- Internal transfers do not have fees;
- API is required;
- Multi-currency;

Thank you!