Securing your iPhone or iPad is more than just setting a passcode. CNETUsing Apple's Touch ID or Face ID tech to secure your iPhone or iPad is something everyone should do. By requiring your phone or tablet to scan your fingerprint or face before unlocking, you're ensuring no one gains access to your device, be it a nosey roommate or a thief.  But even when your iPhone or iPad is locked down, there are still some apps and device settings that anyone with physical access to your device can tap their way through. For example, it's possible that someone can reply to a message from your lock screen without ever unlocking your phone.  Scary, right? Here are three settings you should change to completely lock down your iPhone or iPad right now. Don't show notification contents on the lock screen If you have a newer iPhone that uses Face ID, you may have noticed notifications on your lock screen are hidden until you pick up your phone and unlock it using your face.  You can take this security feature one step further by telling your Apple device to never reveal the contents of a message. Instead, you'll see that you have an alert from a specific app and tapping on it will open it.  Doing so will keep prying eyes from seeing what your incoming emails and messages say. To double-check your settings or make a change to Settings > Notifications > Show Previews and pick either When Unlocked or Never. Always will, as the name implies, always show the content of your notifications even when your phone is locked.  Angela Lang/CNETLimit what can be done on your locked iPhone or iPad Here's arguably the most important part of completely securing your Apple device. Go to Settings > Face ID/Touch ID & Passcode > enter your passcode and then scroll down to the section labeled Allow Access When Locked.  There you'll find a list of different device features, ranging from things like Siri and Today View to Control Center and Wallet. Every feature with the switch in the on position can be accessed directly from the lock screen, even when your device is locked.  For instance, I was able to pick up my wife's phone, hold in the side button to trigger Siri and tell it to send a message or make a call. I could also swipe to the right across the lock screen to view her Today View page, where she has widgets that included her day's agenda and other personal information -- all while the phone was locked.  Go through this list and turn off any features you don't want anyone to have access to. I suggest turning off all of them if you really want to keep your phone and its information locked down. Leaving something like Home Control turned on may seem innocent, but depending on how many and the types of HomeKit devices you have, someone could control your smart home. Thankfully, Apple requires authentication before you can unlock a door or open a garage door.  Sarah Tew/CNETReady to go to an extreme? Turn on Erase Data This should be something you only do if you regularly back up your iPhone or iPad and can get your information back without any issues.  Brett Pearce/CNETGo to Settings > Face ID/Touch ID & Passcode > enter your passcode and then scroll the very bottom of the page. Slide the switch next to Erase Data to the On position.  With Erase Data turned on after someone incorrectly enters your device's passcode 10 times, it will automatically factory reset itself.  The process isn't something that takes place in just a few minutes. After a few incorrect attempts, your phone or tablet will set a time limit before someone can retry to enter your passcode again. After another failed attempt, the time between attempts will be extended. For someone to reach the 10 failed attempt mark would take 1 hour and 36 minutes before the erase feature would be triggered. Now that you have more control over what kind of data and apps can be accessed while your phone is locked, make sure to take a few minutes to tidy up your privacy settings as well. It's a good idea to turn on the Find My feature on all of your Apple devices so you can find a lost or stolen phone (now with peace of mind that someone can't access a thing).