How to set my app as contacts default app in android programmatically

Question

I have developed an android Contact application (To view, edit, delete and call contacts) How can I set an app as default in android programmatically?

please help me, Thanks in Advance.

Answer 1

There's no notion of a "default contacts app", if your app can handle certain intents (for example adding a new contact) Android will show an app selector dialog to the user asking which app they choose to complete the action, the user can also select that app to be used automatically in the future.

If your app is also a Phone app, then there is a way to ask the user to make it the default Phone app, see: Replace default phone APP

If you're referring to the "Contacts" app launcher on the user's homescreen, there's no way to make it launch your own app, you need the user to manually remove the existing launcher and drag your app to their homescreen in its place.