App Lock
Ask for a fingerprint or your phone PIN before the book opens — so an unlocked phone in someone else's hand still shows nothing.
Your book is already encrypted on the device. That protects the file — someone who copies it off your phone gets nothing readable.
App Lock protects the screen. Without it, anyone holding your unlocked phone can tap the Businessly icon and read every balance.
Turning it on
Go to Settings and find Privacy. Switch on App Lock.
From then on, Businessly asks for your fingerprint, your face, or your phone's PIN before it shows anything.
Your phone needs a screen lock first
App Lock borrows your phone's own lock, so your phone has to have one. If your phone has no PIN, pattern, or fingerprint set, Businessly will tell you and offer to open your phone's settings so you can add one.
Fingerprint or PIN — it remembers
If your phone has a fingerprint (or face unlock), the lock screen offers that first, because it is the quickest way in.
Underneath it there is always a way to switch: Use PIN instead. Tap it if your finger is wet, or the sensor will not read, or you simply prefer typing.
On a phone with no fingerprint, there is nothing to choose: it simply asks for your phone PIN.
Choosing when it locks again
Under Lock after you decide how long Businessly may sit in the background before it asks again:
| Choice | Good for |
|---|---|
| Straight away | The strictest. Locks the moment you leave the app. |
| 1 minute | The default. Answer a call or check a message without re-authenticating. |
| 5 minutes | Hopping between apps at the counter all day. |
The hidden benefit: no preview, no screenshots
While App Lock is on, two more things change:
- Your book cannot be screenshotted.
- Your book does not appear in the recent-apps preview — the small live picture Android shows when you swipe through open apps.
That second one matters more than it sounds. Without it, someone flicking through recent apps can read your balances without ever opening Businessly, so no lock screen would ever have been shown.
On Windows, App Lock asks when you start Businessly, using Windows Hello or your Windows password. Windows has no equivalent of the screenshot and preview blocking above.
What App Lock does not do
Being straight about the limits:
- It does not protect against someone who has full technical control of the phone — a modified or "rooted" device. It is a door, not a vault.
- It does not encrypt the files you export yourself. A spreadsheet you export is a normal file on your phone.
- It does not replace a backup. See Backup & restore.
For where your data lives and what leaves the device, see Your data & privacy.