My primary phone is a Samsung Galaxy S3 running Android 4.4.2 Kit Kat. It’s a little old at this point, but I’m disinclined to upgrade for the sake of upgrading. It was getting slower, so I’ve recently taken a number of steps to tune and optimize its performance.
Things I’ve done to make Android slower
1. Enable device encryption
If someone were to steal my phone without encryption, they would be able to hijack any number of my online accounts through email password resets. This is a frightening possibility, and the surest way to protect against it is to encrypt your device.
Device encryption would be mandatory if I chose to access work email on phone, but that is something I choose to avoid.
2. Encrypt microSD storage
Samsung Galaxy S2 through S5 were fantastic phones in that they have replaceable batteries and expandable storage. I’ve recently added a high performance 32GB microSD card to my phone, and sensibly encrypted it.
Things I’ve done to make Android faster
1. Replace Samsung keyboard with anything else
Ever since I purchased my phone, it’s had an infuriating multi-second delay in bringing up the Samsung touch keyboard. I’ve recently switched to the Google Keyboard available in the Google Play app store, and the difference is night and day. The Keyboard comes up instantaneously.
I’ve also heard great things about Swype.
2. Clear caches with CCleaner
Back when I was a Windows user, CCleaner was the one reputable, malware free application for tuning Windows. They have an Android version that does a good job of clearing the many caches and temporary files of your Android apps.
3. Delete all photos
Dropbox automatically backs up all of my photos, so there’s absolutely no reason to keep them on disk. Having a full file system on your Android phone reduces file system and encryption performance.
I went into the Gallery app and bulk-deleted all my old photos.
4. Move applications to external storage
The built-in storage on your phone is not as performant as a quality microSD card. Many applications will let you relocate them after installation to the microSD storage.
5. Disable animated transitions
You can enable developer mode on Android without jailbreaking.
Once you do, you can go into Settings > More > Developer options and disable all useless animations. This is something I’ve done in the past on other operating systems. On Android, I again got better responsiveness and minimal difference in visual experience.
6. Get an extended battery
Samsung phones other than the newest Galaxy S6 have user-serviceable batteries. That means you can easily purchase a replacement battery, an external spare battery charger, or an extended battery.
Since I’ve gotten an extended battery, my phone lasts two whole days on a single charge. This is fantastic for my user experience.
Going beyond
One thing I haven’t done is root or jailbreak my device. If you do jailbreak, you can uninstall all the bundleware cruft that Samsung puts on the phone.
Note that if you do intend to use your phone to access work email, there may be a policy against jailbreaking your device.