How to Encrypt Your Android Phone
When the information on your beloved Android phone must be really, really secure, you can take the drastic step of encrypting its storage. There’s a rumor that the secret recipe for Coca-Cola is held in such a manner.
Before considering this option, be aware that it’s not currently possible to remove encryption. After encryption is applied, it’s stuck forever like a regrettable, drunken tattoo.
Start the encryption process by applying a secure screen lock, such as the PIN or password.
Second, ensure that the phone is either plugged in or fully charged. Encryption takes a while — up to several hours if your phone’s storage is rather full — and you don’t want your gizmo pooping out before the process is complete.
Third, follow these steps to encrypt the phone’s internal storage:
Open the Settings app and choose Security.
On some Samsung phones, choose Lock Screen and Security and then Other Security Settings.
Choose Encrypt Phone.
If you haven’t already done so, you need to charge the phone or set a password or both.
Tap the Encrypt Phone button.
Once encrypted, only by unlocking the phone can anyone access its storage. Further, you need to work the screen lock every time you turn on the phone.
You may want to consider not encrypting your phone but to instead use a strong password.