In a world plagued by data caps and slow-to-respond telecoms, using your Android device as a mobile hotspot can be a dangerous game of cat and mouse between you and the background download actions of the system and various apps. In order to limit this issue, Android 4.1 comes equipped with a little known feature which allows you to designate mobile networks beforehand and customize the options that the attached devices must follow if they want to stay connected.

If both devices are running Jelly Bean (Android 4.1+), the one looking for a connection will automatically know it's hooked up to a hotspot rather than a WiFi router. However if you're trying to run a Mifi or non-Android tablet/phone/music player, you'll need to make sure Android knows to place a limitation on them ahead of time. Go to Settings > Data Usage, and hit the three dots in the top right corner. From here, press the button labeled Mobile Hotspots, and check off the mobile hotspots in your list of saved networks.

From here on out Android will limit the data usage on your selections by default. Music streaming apps won't activate in the background, and mobile data restrictions you've set on the phone will apply network-wide to anyone who's tethered up.

Source: AndroidCentral