There's no possibility of an extension, and it wouldn't help even if there was.
The delay you see if almost certainly due to having to load the script from the Google server.
You will have to somehow deal with the possibility that the device is off-line and has no Internet access. If your app hangs in this situation, Apple will reject it from the App Store.
You need to carefully think-out your use of online APIs like Google Analytics, Google Maps, etc. and make sure that they don't interfere with offline use.
You're creating a native app, not a website!
You might want to research other analytic services that are more well-suited for use with mobile apps.