jee-esteke

Here's a simple example of what I do with the app "MacroDroid" on my cellphone, an app with which you can create...well, as the name it already says...macro's.

I created 4 macro's as seen on screenshot 1.

The first macro (under 2) describes what I automatically do when my phone connects to my home/work wifi (5 SSID's)

Under 3 you see the opposite: what does the phone do what I disconnect from my home/work wifi (5 SSID's)

Under 4 you see what happens when my phone detects the BlueTooth of my car when I push the start button.

And finally under 5 you can see the macro that gives you the actions when BT is disconnected.

So, what actually happens is the following:
When I leave home and go down to the garage in the basement, my wifi is not strong enough downstairs so my phone gets disconnected.
Macro 3 then turns on Mobile Data and BlueTooth.
When I get into the car and turn on the ignition, the cars BT is then recognized by the phone, so macro 4 performs some actions. The text of the actions is pretty clear I think.
Once I get at the office (or back home, depends on what SSID you put in), I shut down the engine, BlueTooth is disconnected and macro 5 does again some actions.
When I enter the office, the wifi signal of the office (or home) is recognized again by the phone and macro 2 disconnects the Mobile Data and the BT.
It's that simple.

I use this program for lots of stuff. Try it out, it's pretty cool...