iOS does not support Flash. If you want your site to work on mobile devices, replace Flash with HTML5 or at least include an HTML5 fallback to support that ever-growing group of users.
It’s true that the average web site’s size has surpassed 1MB. But it is also true that most web sites are excruciatingly slow and unusable on mobile — mobile being the future of web browsing.
Be among the best. Keep your pages smaller than 500K.
You don’t want users staring at a white screen. Confirm that Start Render time is within 2.01 seconds. (Please remind me to justify this number I am now offering as a rule of thumb with no explanation.)
WebPageTest.org can tell you Start Render time as well as a lot of other useful information. Waterfall charts — which WebPageTest.org will generate for you — indicate Start Render time as a first vertical line, usually blue.
If Start Render time is greater than two seconds, you will need to optimize.
This is especially important for mobile devices that show customized keypads and widgets for different types.