objective c - How much RAM is there in an an iOS (Iphone/iPad/iPod Touch) Device?

Question

Different iPhones have different published memory 4GB, 8GB and 16GB. The touch can have 32GB. My understanding is this is the off-line memory (disk alike).

How much actual fast ram is there in the device available for my Cocoa Application?

Is there a preconfigured virtual amount?

Answer 1

iPhone

• iPhone (June 2007): 128MB
• iPhone 3G (July 2008): 128MB
• iPhone 3GS (June 2009): 256MB
• iPhone 4 (June 2010): 512MB
• iPhone 4S (October 2011): 512MB
• iPhone 5 (September 2012): 1GB
• iPhone 5S (September 2013): 1GB
• iPhone 6 (September 2014): 1GB
• iPhone 6 Plus (September 2014): 1GB
• iPhone 6S (September 2015): 2GB
• iPhone 6S Plus (September 2015): 2GB
• iPhone 7 (September 2016): 2GB
• iPhone 7 Plus (September 2016): 3GB

iPod touch

• 1st generation (September 2007): 128MB
• 2nd generation (September 2008): 128MB
• 3rd generation (September 2009): 256MB
• 4th generation (September 2010): 256MB
• 5th generation (October 2012): 512MB
• 6th generation (July 2015): 1GB

iPad

• 1st generation (April 2010): 256MB
• iPad 2 (2011): 512MB
• 3rd generation (March 2012): 1GB
• 4th generation (November 2012): 1GB
• iPad Air (November 2013): 1GB
• iPad Air 2 (October 2014): 2GB
• iPad Pro 12.9" (November 2015): 4GB
• iPad Pro 9.7" (April 2016): 2GB

iPad mini

• 1st generation (November 2012): 512MB
• iPad mini 2 (November 2013): 1GB
• iPad mini 3 (October 2014): 1GB
• iPad mini 4 (September 2015): 2GB

Apple Watch

• 1st generation (April 2015): 512MB

Apple TV

• 2nd generation (2010): 256MB
• 3rd generation (2012): 512MB
• 4th generation (2015): 2GB

iOS doesn't use swap space, therefore, only RAM will be available to processes. (That said, iOS does support paging executables.)