No, just unlockables.
The devices you can play Batman: Arkham City on are: Playstation 3, Xbox 360, and PC. If you want to play the Batman: Return To Arkham - Arkham City, then you need a Playstation 4 or an Xbox One of any kind.
You can play the catwomen story missions when you playthrough the storyline normally. Then once you have completed them you can replay them from the main menu. You can also switch to play as her from any of the switch points throughout Arkham City.
OH Yeah theirs lots Of those gta batman arkham city
No.
no
there probably are but none that I know of
Do any side missions or find riddles if you did that just fight thugs or find secrets to get started go on the boat and try the hacker at different areas and you get a Scarecrow secret
No. There are no cheats.
At the moment they are not making any more games. In an interview on Major Nelson's show with one of the developers of Batman: Arkham Asylum they said that at the moment they don't know what they are going to do next.
If you have any other version than the PC version you can't. The Beyond suit is only a PC mod, it is not an unlockable item in the game.
On the main menu, instead of selecting 'story mode' simply go right one icon to the one resembling a question mark. This area is run by The Riddler and that's where you can play challenge maps with Batman or any other downloaded character.
Not necessarily, I certainly would recommend playing Arkham Asylum first as their are pieces of the story that also tie into the sequel,but on the same token everything that happens inside of Arkham City is also stand alone so you could jump straight into the sequel without much confusion. Even if you are familiar with the Batman Mythos there are a few examples of brand new characters being introduced within Arkham Asylum. All in All if you are debating about playing both simply play both. I'd recommend playing in chronological order but is playing them in order a necessity,no you can play in any order and not risk much confusion or much spoilers to the previous game other than its ending.