I worked for a US client on an android app. I...

Kindly, could you clarify your question in details so we could help you legally better with pleasure.

According to the facts before us and as long as the electronic work is agreed without the existence of a contract of employment, the legal location of the contracted party is very weak verbally, and that what you are exposed to is a threat and extortion to refund the amount paid for your work and your effort and therefore there is no other way to recover The amount in a legal manner since there is no evidence by them to transfer any money,

So, they resort to these methods to try to recover the amounts paid illegally and this by pressing you and using methods of intimidation and intimidation,

So, your legal situation is certainly good, as long as you send the work to the concerned party and you undoubtedly keep a copy of it, as well as proof of your submission,