Have you ever seen an iOS device as it displayed a notification, that the screen lights up and the notifcation is displayed on the lock screen, and thought to yourself that you want to see this happen on your Android device? Well, I did and thus createt this app - Notify Me!
Notify Me! is simple in design: You add apps of which the notifications should be displayed on the lock screen to a list, specify¹ the behavior of those notifications on the way and wait for a notification - it will be displayed as a popup in front of your lock screen.
¹No worries, the default behavior should suit most people's needs:
-Popups will only be displayed if the screen is off locked.
-Notifications will light the screen up.
-On Android 4.1+, popups of notifications that provide a bigger view will be expandable.
All of these settings can be customized! It is, for example, possible to make notifications just light up the screen, without showing a popup or to don't let notifcations light up the screen, with a popup waiting for you to manually turn the screen on, etc...
Generic aspects of popups can be customized, too. You can choose between a user interface with buttons and a user interface with a slider for interactions² with the popup. You can even set a custom screen timeout for cases when notification popups lit up your screen and you find your systemwide screen timeout to be too long for this popups.
²These interactions are possible: You can view the notification (this unlocks the screen and is effectively like tapping the actual notification in Android's notification area), dismiss the popup (unfortunately it is, as far as I know, no possible in Android to dismiss the actual notification this way) or expand popups of notifications that provide a bigger view (of course, only on Android 4.1+).
The only thing you'll have to do in any case is to enable Notify Me! as an accessibility service! Because there has been a lot of trouble with this in the test phase, Notify Me! will check on every app launch if it's accessibility service is running properly and provides you with a shortcut to the corresponding settings screen, if necessary. How often there will be a need for this depends strongly on the implementation of accessibility services in the Android build you are running! Whilst, during development, I only had to enable it once after the initial installation on my HTC Desire Z running CyanogenMod 10.1, I needed to enable, disable and re-enable it on my Sony Xperia Z (with stock Android 4.1.2) after the initial installation and need to disable and re-enable it after every reboot of the phone or update of the app - your mileage may vary! This inconvenience is, as far as I know, not my fault and either a bug or a security feature in some Android builds.