Any reputable one that does not require KYC, for example WOS, Coinos or Blink (the latter using a phone number without KYC, although you can later remove it and put an email without KYC).
Discussion
How do you get the @walletofsatoshi address ? Does the app give that when you register with another email?
You create a fake email account or use a service like hide my mail and you will be able to create your custom address after receiving or sending 10 payments and sending or receiving 100000 Satoshis onchain, if you don't do that you can use the random address that is created by default.