Why do apps open up when I start up Bluetooth?

Episode 1557 (1:00:04)

Tom from Toronto, Ontario, Canada
Smartphone and computer

When Tom turns Bluetooth on after having been turned off for awhile, tons of apps start opening up on his phone. What's happening? Leo says that backgrounded apps automatically terminate after a short period. Leo recommends letting the phone manage his apps for him. He doesn't need a third party app to kill them — he should just let the phone do it.