Sprite size for Mobile game

Hey,

I want to make a game that I can publish on IOS/Android devices, I read article on supporting multiply resolutions and I think I got the construct side of thing, but i was wondering what size should I base my sprite sizes on?

Should I make sprites to work 1x1 on Largest device (for Ipad 3/4 1536x2048) and let it downscale on Ipad 2 and Ipad 1 or is it better to AIM for smallest resolution or midresolution? so they scale up

or what is best practice to handle that?

I designed game originally with ipad3 resolution in mind but eventually i got project that crashes on cocoonjs app preview and memory usage at the bottom shows 300mb, so I'm worried I might have taken wrong approach here ;/

For a mobile game, I like to design everything for the largest resolution that I'll be supporting. That way the game still looks great on the larger devices, and doesn't lose much of its quality when it gets sized down.

I got 300mb memory usage that way

when I resized to 1024x768 and trimmed some animations I now have 47mb memory usage (status bar of construct)