Let LED Blinker Notifications (formerly LEDBlinker) show your missed calls, SMS, Facebook and Whatsapp messages. If you have no hardware led, the screen is used.
Only some applications are supported by the lite version, see advantages of the full version below!
All apps are supported in the full version, click on the plus button on the top and add the missing.

Its possible to remove the ADS (see the button at the top or at menu) but you WON'T get the FULL VERSION!

This app is very simple to use and not much configuration is needed!

Functions:
✔ Works with latest Android Lollipop/Kitkat/Marshmallow/Nougat Version
✔ individual settings for each app, e. g. blink rate, vibration, sounds and repeats
✔ Silent mode for every day (enable it for the night to stop blinking
✔ Screen LED for phones without real LED

Examples for apps with notifications:
✔ missed calls and sms
✔ Battery status (LED notification for low battery, < 10%)
✔ Google Mail
✔ Google Talk/Google Hangouts
✔ Calendar reminder notifications
✔ Standard EMail App
✔ Bluetooth messages (LED goes on when bluetooth is active)
✔ Alternative On-Screen-LED

Advantages full version:
✔ All apps are supported
✔ Facebook messages
✔ WhatsApp
✔ Contact specfic colors for WhatsApp, missed call, Telegram, Signal
✔ Save battery with pocket mode
✔ light and dark color scheme
✔ export/import settings (no lost settings when you install new ROMS/mods)
✔ widget to deactivate LED Blinker/remove notifications quickly
✔ Skype messages
✔ SNOView - Social Network Overview notification
✔ Twitter, Threema (now with group support), Facebook Messenger and so on.

Blackberry user should know such apps like BeBuzz or BerryBuzz - this is the solution for Android.
IPhone/IPad doesn't allow such an app.

* AndroidHeadLines: 'LED Blinker is an Android app that aims to make it much easier to help you figure out which notification is which'.
http://androidheadlines.com/2014/12/sponsored-app-review-led-blinker-notifications.html

Unlike other apps in this category you don't need 'ROOT' access to use LED Blinker and this app is very battery friendly!
All rights are needed to run the app, lesser are not possible.
The new right to write to SD card it needed for error reports (check menu extras: Debug mode), please send it to mosoft.android@gmail.com if you have found an error.

Facebook
http://goo.gl/I7CvM
Google+
http://goo.gl/5XBdN

Please try out the lite version at first to see if your hardware LED works (on screen LED is always working!).

Please check device specific hints at the end!

Fast support is very important for me! (Look at the ratings, thanks to all people!)
If you have problems please do a full re-install and/or reboot your phone.
Otherwise contact me at Facebook/Google+/Email to get help.

Warning: If your phone speaks after install (Samsung S4, SIII, S3 Mini, S2, Note1, Note2, Note3, LG Nexus 4) you have to disable Samsung TTS (text-to-speech) under settings -> apps manager -> all (on the right) and Google TTS (text-to-speech).
Only needed when you use the accessiblity service!

Another solution to fix talkback issue:
You can change the launcher by using another one from the Google Play Store. For example, Solo Launcher - Swift & Smart, Nova Launcher, Go Launcher and Holo Launcher. These launchers will not exhibit this bug.

For Samsung S4 users: If your phone speaks when opening your browser you have to use another browser like Chrome or Firefox.

Hint HTC users: Your phone is NOT supported, you have to use the on screen led!

Sony Phones: Please disable stamina mode in your device settings.

Let your led indicator glow with different colors!

BETA Test:
https://goo.gl/66v6R5
https://play.google.com/apps/testing/com.ledblinker