I've already wrote a list of 100 Must Have Apps for Android Phones, but most of these apps are for "Android-Newbies", some for users with rooted phones, but here's mini list of the best of the best, extremely useful apps that will help you to make full use of your Android phone:
I've been using JetAudio for PC for years now it's an awesome player and recently and Android version was released, I had it on my phone for a while before i started using it because I got used to the S2's native music player but when i started using it, I discovered many great features that you rarely can find in other Android music players this app allows you to play songs by Artist, Album, All songs, Folder (which was only available in the Samsung's native Android music player), Playlist or genre, the equalizer is pretty awesome too ! it gives you almost all of the PC features and i hightly recomend it
Album Art Grabber
The title makes it clear, This app downloads the missing album art for you an set it up automatically.
Alarm Clock Extreme
The most reliable and alarm clock App you can find in the Google Play app store! I've been using my Samsung Galaxy S2's stock app Alarm clock to wake me up and to be honest something is just not right with it ! I don't understand why, It has never woke me up but hey, I am a very heavy sleeper tho, sometimes I even answer calls in my sleep and never have any memory of that when I wake up ! so may be I wake up turn off the alarm and go back to sleep right away... but with this app you can set simple math problems to solve in order to snooze/dismiss the alarm and many other awesome options.
VLC Direct Pro Free
This is one of the collest apps I have used so far ! it allows you to remote control VideoLan VLC from your Phone/Tablet (play, pause, stop, volume, fullscreen, change video/song, dvd menu control, change audio tracks, change subtitle tracks, etc.) an to stream from Android to Computer (Video, music and photos).it might be a little hard to set up for some users but it's totally worth it.
This is a video player that allows you to play videos in a popup floating window with re-size, move window, two multi-window play-back ( A feature that was introduced in the Samsung Galaxy S3)
LBE Privacy Guard
Basically it lets you controlling the permission of each application to access your sensitive data. an app that I consider essential to every ROOTED Android device, and it was one of the reasons why I downgraded from Jelly Bean to ICS because it's not yet compatible with Jelly Bean. Highly recommended.
Backup your apps directly to flashable zip file, If you are like me and like to try a different ROM on your android phone every once and while, you had this problem of either having to re-install all of your apps from the Google Play all over again or install one by one from the back up you created on your SD card, but not with App2Zip, this app allows you to backup all of your apps into one file so you can restore them all in a couple of minutes without having to click on anything, it's very simple and easy to use.
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