I'm making the mobile version of an online store and i have to make it available when offline.
The problem is with photos: the store might have a large number of products, thus photos.
What method of saving the images should i use considering that a phone has some hardware limitation?
What I want is
As small as possible occupied memory with ok performance at reading it.
Writing speed is also something to be considered since downloading so much data will take some time and the user might decide it's not worth the wait(this is a secondary problem though).