Can I send some info to apple watch from iOS app using Watch Connectivity if apple watch inactive?

Question

I have iOS app and watchOS, I need to get some info from iOS app to watchOS, when apple watch opens in first time.

User opens iOS app -> get userID from backend -> after some time opens apple watch -> get info from backend using userID from iOS app

How can I do this?

Keychain with iCloud doesn`t fit me. Any other ideas?

Answer 1

Yes, when there is an active session. The docs say:

Most transfers happen in the background when the receiving app is inactive.

Specifically, when a watch session is active, you can use

• updateApplicationContext(_:) This function transfers some info, but overwrites any previously sent application context.
• transferUserInfo(_:) This function is used, if all transferred data are needed, i.e. previously sent data are not overwritten, but queued.
• transferFile(_:metadata:) This function is used to transfer not a user info, but a file.
• transferCurrentComplicationUserInfo(_:) This function transfers data to update watch complications.

All of them work in the background.