To change the PIN or password (from now on referred to as "PIN") that protects opening and transacting with your Koala Wallet, press the Eco button at the bottom of the screen.
At the top right hand corner of the screen press the settings ⚙️ icon
Authenticate with your PIN or biometric, and then select "Change wallet PIN".
Set a new PIN, then repeat it to confirm you memorized it.
This is a privacy feature to prevent others from viewing your balances and transaction history. By default, Koala Wallet locks itself instantly whenever it leaves the foreground. Authentication will be required every time it's re-opened. If you feel that this is too inconvenient, you can change this behavior in the Auto-lock menu.
The default value of "immediately" requests authentication every time you open Koala Wallet after it was sent to the background or minimized.
By choosing any of the timed options, your wallet will only be locked after it has been in the background continuously for that long. You won't have to constantly unlock your wallet for example if you're quickly switching back and forth between Koala and different apps.
By choosing "never", after a device restart, the PIN lock only needs to be passed once. After that, anyone with access to your phone will be able to see all your wallet's balances and transaction history.
In any case your assets are always protected. Besides the first time the app is opened, authentication is always needed for sending transactions, as well as for viewing and changing sensitive settings.
The Browser Extension version has a lock button, for example in case you set a long auto-lock value but you need to leave your computer unattended. On the initial screen, press the padlock icon at the top right corner and Koala Wallet will immediately lock.
This is currently not available on the Browser Extension version. In the Security section you can also set the biometric option. Simply use the toggle switch to set your preference.
With this option enabled, you can use your device's biometric sensors (fingerprint reader, face scanner) instead of entering your PIN to unlock the wallet or make transactions. Be aware, even with the option enabled you are still expected to remember the PIN, as it may still be required in certain occasions.