The nice folks behind Conversations.im (IMHO, the best IM service/client for Android) have released Quciksy, a variant which synchronizes contacts using your phone number (like WhatsApp).
If you have a few minutes to spare, take a look at it:
Why is this step necessary? mstdn.io might not be the server where you are registered, so we need to redirect you to your home server first.
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