yes
Yes, you must have an active internet connection on your iDevice to play DragonVale.
Not all but most of them require internet connection.
No. (Obviously, online multiplayer does require an Internet connection.)
Yes, you must be online to play DragonVale.
Command and Conquer does not require internet connection to play However, Command and Conquer 4: Tiberium Twilight can be quite strange if you do not have a constant internet connection while playing.
you should be able to play it offline like ps3 and other consoles that doesnt require internet connection
Doodle Jump is primarily a single-player game and does not require an internet connection to play. However, it does offer online features such as leaderboards and the ability to share scores, which require an internet connection. Overall, while you can play the game offline, some functionalities depend on being online.
Online is the only way to play Dragonvale!
It depends on the app. Some like Skype or Facebook will not work without an internet connection to work. Some like Evernote can work with or without an internet connection but will require you to connect at some point. Some like the Angry Birds game do not require an internet connection to work. All apps will need to be installed somehow and the most common way to install an app is by downloading it from the Google Play store. So, the answer to this question is - it depends. So do, some dont.
You need an internet connection to play online only
no you can play with no internet :)
In Age of Empires 3, you only need an internet connection if you want to play with other people online with an ESO (Ensemble Studios Online) account. To play single player skirmishes and/or campaigns, you do not need an internet connection.