You can use Instant Hotspot on your iPhone (with iOS 8 or later) or iPad (Wi-Fi + Cellular models with iOS 8 or later) to provide Internet access to your other devices (iOS 8 or later) and Mac computers (OS X 10.10 or later) where you’re signed in to iCloud with the same Apple ID. Instant Hotspot uses your iPhone or iPad Personal Hotspot, without you having to enter a password or even turn on Personal Hotspot.
Use Instant Hotspot. Go to Settings > Wi-Fi on your iPod touch, then simply choose your iPhone or iPad network under Personal Hotspots. On your Mac, choose your iPhone or iPad network from your Wi-Fi settings.
When you’re not using the hotspot, your devices disconnect to save battery life.
Note: This feature may not be available with all carriers. Additional fees may apply. Contact your carrier for more information.