In continuation of my former answer, some other useful automation apps are:
It is a paid app with 10 day free trial version. Use the trial version for testing before attempting to buy the app from store.
Alike Automate, it uses the concept of flowchart. You would have to create a flowchart like this
(Click image to enlarge)
The block with rounded edges represents a trigger, the rest are for actions. The app would introduce your with its know-how, so you would know where to look for to create that chart.
Note that Execute Command is executing the command
sleep N. Replace N with the number of seconds your timer would have, such as 360 for 6 minutes.
It is a paid app with 7 day free trial.
The information about the intent and variable wifi_state came from this reddit thread by TremendoSlap. Anyhow, if you monitor the output of logcat when hotspot gets activated, you would know that the said intent is broadcasted with initial tethering state denoted by 12 to final state 13.
It is a free/paid app. Free app would be enough for our goal.
Create a profile with following entries:
- Trigger: Wi-Fi Hotspot state → Become active
- Various → Sleep → set timer duration
- Network → Wi-Fi Hotspot → Disable
Everything works fine except that sleep duration cannot be beyond 10 seconds in a task. The simplest workaround is to add multiple tasks with sleep action. It may become impractical to add multiple of such tasks. Hence, you may consider Tasker here.
Under Various there is an option to execute Tasker's task. The Tasker's task would be to wait for N seconds/minutes and turn off Hotspot.