Well you can replace your voice assistant Siri and use google assistant as default instead of Siri on your iPhone/iPad only if you are jailbroken on iOS 10, 10.1.1, 10.2.
You need to press and hold the home button to access google assistant same like as Siri. To make more convenient that using an google assistant app you can replace Siri with google assistant on iOS 10,10.1.1 jailbreak.
How to Replace Siri with Google Assistant on iPhone in iOS 10
You can only replace your default Siri or Voice control with Google Assistant completely if your iPhone/iPad is jailbroken on iOS 10,10.1.1.
With Activator, you can make Google Assistant as default voice assistant which function same like as Siri. You can do lot more things on your iPhone from Activator.
If you want to use Google Assistant as your default voice assistant instead of Siri on your iPhone/iPad running iOS 10 or higher, simply follow these steps;
Follow these steps to replace your default voice assistant Siri with Google Assistant on your iPhone Before you begin, go to Settings app and tap on Siri >> Toggle off the switch to disable Siri completely.
Step 1: Download Google Assistant from the App Store and Activator from Cydia.
Step 2: Now Open the Activator Cydia app from the Home screen.
Step 3: Tap on Anywhere option from the list.
Step 4: Under the Home Button section, tap on Long Hold.
Step 5: Scroll down to the User Applications section and under Google Assistant option,press on the ” i “button and select ‘Open App Immediately’.
That’t it! You have success fully replaced Siri and made Google Assistant as your default voice assistant on iOS 10 jailbroken iPhone/iPad.
Now when you press and hold the Home button, it will open Google voice Assistant as default instead of Siri.