Amongst the Apartment Therapy team, we've got both Android and iOS users (even a couple of Windows Phone 7 users, if you can believe it). And with our extensive long term experience with both of the major platforms, our verdict is: it doesn't really matter.
In our experience, the most common use amongst everyday users for Flash is watching embedded videos. Since the majority of the videos posted are from YouTube, we don't really have an issue watching those videos. And other video hosting sites such as Vimeo have followed suit and embraced HTML5 as the new standard for video playback. We actually prefer using the finger-friendly iOS controls to watch videos. Trying to peck away at the teeny-tiny YouTube controls ruins the tablet experience. So in our opinion, in terms of web video, you won't be missing anything if you're on an iOS device.
That being said, if you're really committed to watching/using Flash on your iOS device, there have been some work arounds using jailbroken devices permitting Flash use.
Multitouch on Android tablets with the Flash controls are still glitchy. And try watching a YouTube video that is embedded on an Android device, the controls are so small that we often miss the iOS experience. The experience on a smartphone even more painful that we usually just give up and use our laptops.
With the web transitioning to a new standard and the major players in the industry committing to HTML5 (note the lack of Flash support on WP7 devices), we surely will miss Flash less and less. For now, Android users frustrated with the Flash experience on the stock browser can check out Skyfire browser. Skyfire uses the power of cloud to transcode Flash videos into HTML5 codes, making the controls more finger friendly.Or simply download the native apps from sites such as YouTube and Vimeo.
What do you think about having Flash on your mobile devices? Is it essential or is it secondary? Let us know in the comments below!