Originally Posted by Nokia N93
I'm newbie with android systems and im new here in your website, i have Galaxy S4 and i want to ask the most popular application that i must have
also i want to ask how can i backup my contacts and save them to my email or in my PC.
thanx in advance
Welcome to Android and XDA.
Don't forget to glance over the forum rules and always check out the stickies posted in each forum section (they have a thumbtack image next to them and never move from the top section). They contain valuable info for newcomers.
Both your questions are really all about personal preference. No single app's importance is the same to everyone. My advice to you being new to Android and all is to go into Google Play Store and just browse the list of top paid and free apps. This will give you a good idea of what a majority of users are downloading and using the most. Likely there will be numerous apps in there you will find beneficial. Remember one thing though, rooted users have more app options than non-rooted so just keep that in mind. Some apps require root access and will state that in the description. Once you use your device a bit more you will get a feel for what type of tasks you do most often and what apps might make the experience better.
As for contacts, there are different options for this. I would say since most have a Gmail account to access the Play Store, get email, etc. they will use Gmail to auto backup/restore contacts, calendar, tasks between the cloud and the device. I believe Samsung also will back this up for you which, if you have a Samsung account, is native on the S4 already. To give more direction would have to know what you are using on your PC for mail client, how you are using it, etc.
Samsung Galaxy S4
Samsung Galaxy Note 8
Asus Eee Pad Transformer
My S4 Multiwindow Themes
My Note 8 Multiwindow Themes