My friend is convinced that the slowing of his iPhone 4S is part of a vast Apple conspiracy. I'm not completely persuaded.
I mean, sure Apple has sent out updates to iOS that are arguably a step in the wrong direction, like that whole cruft. Sometimes, you just have to do a little housekeeping.fiasco. But I believe the main culprit for decreasing smartphone performance (from any phone) is software
So here's what I suggest. First, take a minute to get rid of any bulky apps you never use. Dive in to Settings>General>Usage and look at the list of the apps installed on your phone. You'll see them listed in order of the size of the app, which makes it easy to spot the serious offenders. I'll bet you'll be surprised.
As a serious podcast junkie, I was surprised to find several gigabytes of podcasts sitting on my phone. Turns out I had a few of my subscriptions set to never delete old episodes, and they just built up over the years. Games are another source of bloat. They're typically large files and instead of deleting the app when we get bored with it, we tend to hide it away in a folder. That's why this "usage" view comes in handy for shining a light on the apps you've been hoarding. Once you've recognized the problem apps, delete them. You can always download them again later if you really need them. If you notice the iOS Photos app pretty high on the list, it's a good time to back up your camera roll to your computer and start afresh.
Next, clean out the browser. Safari's cache of visited pages and Web cookies probably has more dirt on you than you'd prefer to carry with you. To purge it, head in to Settings > Safari and click the two buttons for clearing your history and your data.
At this point, you could reboot your phone and probably notice a distinct improvement. But here are a few extra tricks to really get your iPhone back in shape.
Try resetting your system settings. It sounds scary, but it doesn't delete any of your phone's contents or rearrange your meticulously arranged apps and folders. Go into Settings > General > Reset and select the top option, Reset All Settings. Do not tap the Erase all Content and Settings -- that would be bad. You'll be given two warnings just to make sure you mean business, and then your phone will reboot with a happier attitude toward life.
It also bears mentioning that the home button on some older iPhones can become less responsive over time. Our own Sharon Vaknin.
So those are my best tips for getting your iPhone back in tip-top shape. If it works out, treating your old friend to awould be a nice gesture.