If your iPhone runs slowly, is short on space, or regularly runs down its battery, you might search the App Store for "iPhone cleaner" or "iPhone booster" or something similar and find myriad apps that claim to eliminate junk files, retrieve memory, and improve battery life. But do they work as promised? I tested an assortment of iPhone optimization apps rated highly by users and was surprised to find them largely useless. Read on to learn what these apps do and don't do, or fast-forward to the end for tips on tidying up your iPhone without another app.

Battery Doctor


Battery Doctor reveals your battery status in a larger typeface than Apple currently provides, along with your memory usage, storage capacity, and added apps, plus optimizing tips. Pressing Boost from the Status page or Memory page cleaned up 788MB of memory and reduced my phone's used memory from 76 percent to 37 percent. Or so I thought. But when I reopened the app, I was back at 76 percent memory used.

To clear out junk, press Clean Now from the Status menu or Clean Up Cache from the Junk page. The app warns you to use this feature only when disk space is seriously low and to back up important data beforehand. However, in my tests, it didn't take my phone down from 43.2GB.

You can also click the top-right menu button and then System for real-time reports on CPU, memory usage, and more. However, it's just info; there are no tools to help you improve these functions.

On the upside, I was impressed with the app's up-to-the minute weather info.

Memory & Disk Scanner Pro


Memory & Disk Scanner Pro presents your Memory and Disk usage as soon as you launch the app. I chose Memory and was given no information. Then when I selected Disk, it informed me that I have 177.68MB of junk files. After tapping One Click, I was told that I have no junk files. With another tap I was told again that I have 177.68MB of junk files. Then with another tap, I was at zero again. A Settings Menu enables you to choose to scan your memory and/or disk each time the app starts up, and you can select how deep you want the scan to go. I just don't see what the point would be.

Battery Saver


Launch Battery Saver and you'll be treated to your current Battery Power percentage at the top left of your screen. Click Memory to see how much memory you have, shown in both percentage and megabytes. I was told that I had just 2 percent of memory free. I pressed Boost Memory, and the app optimized memory to 22 percent. I boosted again, and it told me I had 26 percent. Tap Disk on the bottom rail to Clean Junk, and you receive a message of Junk Cleaned and just how much storage space has been freed. I was informed that I now had 10MB free. I tried again when I saw that I had the exact same amount of junk and was told that now there was 21MB free. This made no sense.

iRefresh Pro


iRefresh Pro provides a breakdown of how much RAM you've used and how much CPU. In my case, it was 1.9GB of RAM and a CPU that kept changing from 11 to 17 percent. I pressed Refresh Memory, and my used RAM dropped to 1.6GB and then went up to 1.7. The CPU kept alternating, going up as far as 35 percent used. Under Settings you can upgrade to a Deep Refresh or Extreme Refresh, which supposedly free up more memory if you review the app on the App Store or pay money. We opted not do this, because the app didn't seem to work.

Mobile Doctor Pro


Mobile Doctor Pro reveals your battery power info. In our case it was at 78 percent. You can even use a cute little pulley to pull down a screen that provides info such as Unplugged Power, the weather, and the time. This screen stays on even when your phone is inactive, although one would assume that this sucks up more power than having your phone in sleep mode. But none of this can hide the fact that most of the app's features aren't relevant. Detect helps you troubleshoot phone issues, such as whether your camera, touchscreen, or flashlight are working. Network tells you your monthly surplus and how much you've used. Privacy enables you to select a password mode. Discover recommends unrelated apps to download. Network Device Scanner tells you which devices are on your network. Countdown counts down to an important day, QR-Code Scanner is self-explanatory, and there's a a Flash Torch -- whatever that means.

There are more relevant features, such as Disk Space, which shows in a pie graph how much space is free and how much is used. The problem was that although I have photos, videos, and MP3s on my phone, the breakdown suggested that no space was taken up by these media. The Duplicate Photos Scanner misread dissimilar photos as duplicates; the Duplicate Contacts Scanner found duplicate contacts but wouldn't merge them; and System Info informed me that I'm using 98.4 percent of my memory, which seems very high. Oh, and there is an alarm to remind you to charge your phone, but probably you can remember to do that on your own.

How to clean up your iPhone

Clear storage

iPhones offer built-in functionality for deleting unwanted data and improving battery life. To clear out unwanted data, tap Settings, General, Storage & iCloud Usage, and then Manage Storage. There you'll learn how many gigabytes you've used and how many are still available. Below that, all your apps are conveniently ordered by size, from largest to smallest. Tap one to get a breakdown of how many kilobytes or gigabytes the app -- and the documents and data within it -- consumes.


If you wish to delete an app, just tap it and select Delete App. If you want to delete the documents and data stored within the app, unfortunately you'll have to open each individual app from your home screen and do it from there.

To eliminate space-hogging history and website data from Safari, tap Settings, Safari, and Clear History and Website Data. You'll remove your history, cookies, and other browsing data. Then scroll down and tap Advanced, and under Website Data you can delete even more.

Save battery

If you're concerned about your battery usage, tap Settings, then Battery, and toggle Low Power Mode on. Low Power Mode reduces power consumption. Certain features won't work in this mode, such as Hey Siri, but it's a huge help if you can't easily charge your phone. You can also scroll down to see which apps are draining your battery.


More Resources

Free up iPhone and iPad space

Transfer your data to a new iPhone

Joshua Rotter is a copy editor for Download.com and covers iOS.