Phone authentication slow?

[dqii]

invertase/react-native-firebase#5316

This issue was posted on react-native-firebase a couple of months back, was wondering if the folks here would have any ideas.

I was trying to sign in with phone number using

auth().signInWithPhoneNumber(phoneNumber, forceResend)

On average, this method takes 7-10 seconds to resolve on ios. (Similar amount of time to receive the sms)

My guess is that Firebase needs to send a Silent APNs notification to the device first before sending the actual sms message. Is there a way to call this method separately ahead of time, so the actual SMS waiting time becomes shorter.

I'm having the same issue, although I notice some live iOS apps that also use Firebase Phone Auth don't have this same issue. Is this typical? If not, are there common things that could cause it?