While this might appear to temporarily "speed up" your device, this kind of "Chuck Norris Roundhouse Kick" is rather contra-productive for the system, especially for two things:
- your battery load
- time to access one of the killed apps again
Android usually does a good job managing ram. But some apps sometimes make it hard to do so (mostly by not behaving properly: hogging lots of RAM and trying to "stay alive" even if the user wishes them to quit). So to have the same "speed-up feeling" without the nasty side-effects, you'd better identify those bad-behaving apps which you killed along the others (like the wild-west saying: "Kill'em all and let the Lord sort out the bad from the good").
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