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I never ever close apps. It is a smartphone. I let the smart part of it do things like that for me. I also never switch off my phone. I guess the only time the apps close is when the phone gets updated or requires the rare restart.

Never had any issues with things like that. I am not bothered by such things. And I use the app switch screen all the time.

But I have to admit that I do have a bit of OCD regarding taking care of my battery life so.... :p
 
I usually swipe them closed. It makes sure online banking apps are killed / logged out immediately. Also, once I've finished with an app, the next time I run it I expect it to open to its home screen or whatever rather than continuing from where I left off.

For apps I use frequently, I just leave them there, however it's much quicker just to swipe everything closed rather than pick individual apps out.
 
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