Blog: Android

Should I enable encryption my Android handset?

Joe Bursell 23 Sep 2015


When we talk about encryption here, we’re talking about Android’s built-in full-device encryption. If you feel that data in your device needs to be protected to a higher level than setting a strong password and making sure that ADB is turned off then maybe encryption is for you.

The good and the bad

Depending on your device and the version of Android you’re running there are lesser and greater prices to pay. Essentially encryption places greater performance stresses on a device than running it unencrypted.

Processor power

This means that older devices and budget handsets tend to become sluggish once they’ve been encrypted as they simply have less processing power to cope with the extra demand than better specced handsets. Devices running non-stock versions of Android, such as Samsung or HTC may be similarly affected as they use different algorithms.

This is a good example where two Nexus 5 handsets running stock Android Lollipop 5.0.1 were tested side-by-side to show how much impact encryption would have. The encrypted device read information on the disk 40% slower than the non-encrypted handset- a sizeable difference.

Battery life

Aside from performance degradation battery life will also suffer. All the extra work that the device needs to do in order to function normally while providing encryption protection means that a device can go from consuming 100% of its battery power in 48 hours to 18 hours.

Can I go back?

Before you enable encryption think about how you can reverse the process if your device becomes too painful to use. Some devices like the Samsung S5 appear to allow you to undo the encryption with no obvious ill effects or loss of data and/or apps.

On the other hand older and lower spec devices can leave you having to do a factory reset as there is no “back to normal” option. This isn’t the end of the world but it does mean that you’ll have to go back and download your apps, and you’ll need to make sure that you’ve backed up your data beforehand too. There’s a nice guide here.

The bottom line

If you need to encrypt your device then by all means go for it, but be aware of the potential overheads in terms of performance and battery life, and take steps to make undoing it less of a challenge should it prove too frustrating.

If encrypting your phone doesn’t work out for you, or you’d just prefer to side-step it then do the following to secure your mobile devices:

  • Always run the latest software version
  • Use a long password over a PIN or a PIN pattern
  • Turn off Wi-Fi when you don’t need it
  • Disable voice control