Tip to speed up performance:I always run my images through PNGYU and it really helps speed things up on devices.
Yep, I do this too. The exports are optimized for speed, not minimal file size by default. Maybe I should make this a built in option.
Isn't this like common standard? Image optimization?
I mean, what you do for web dev is also what you should do like anywhere. Though I wouldn't just use any image minimizer, because they vary in output quality and optimization potential.
I used to use kraken.io for automization in WP projects (after the smush library got limited) and for everything else I basically use a gulp pipe with ImageOptim - no need to care about that though.
On desktop I use FILEminimizer since ~7 years for quick batch cycles.
Here's some more data: