Send SMS on behalf of user in Android [duplicate]

This question already has answers here: Android send SMS which is visible in SMS thread (no GUI) (2 answers) Closed 2 years ago.

What do I need to do to both send an SMS messag开发者_如何学编程e but also have it appear in the user's text messaging apps as if they sent it from the app themselves?

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You can write your own SMS client.

Or, you can negotiate with every SMS client author out there, to get them to open up an API to allow you to put messages in their app that they didn't send.

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SMS messages can be stored in the SIM card of GSM phones. Perhaps these various SMS message apps are all accessing the SMS messages on the SIM card, effectively providing integration between the apps?