The trick? Adding the widget for Google Keep to your Android lock screen.
First, let's make sure lock-screen widgets are enabled on your Android device. Tap Settings > Security, then make sure the box next to Enable Widgets is checked.
Lock your phone, click a button to activate the screen, then swipe left or right from the edge of the display until you see a big '+' button. Go ahead and tap it, then unlock your phone.
Scroll through the list of available widgets, find Google Keep (or your favorite note-taking app), then tap to add it to your lock screen.
Now, lock your Android device again, swipe from the edge of the screen to flick through your lock-screen apps, then tap in the top-left corner of the Google Keep widget to add a quick text note. (Yes, you can also record voice memos with Keep's lock-screen widget by tapping the microphone icon.)
4. Take a video selfie [iOS]
Does getting to that great idea demand a little free association? If so, maybe you'd rather record your freewheeling thoughts in a voice memo than rely on Siri's (sometimes iffy) transcriptions.
Unfortunately, iOS devices don't allow for easy-access lock-screen widgets like Android handsets do. So here's a somewhat unorthodox solution: taking a video selfie.
Why a video selfie, you ask? Because you can access your iPhone's or iPad's camera from the lock screen without having to unlock your device.
Simply swipe the camera shortcut in the corner of the screen, tap the red Record button, say your piece, then tap the button again.
Once you unlock your iPhone or iPad, you'll be able to share the video via email or text message.
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