It's becoming evident in my testing that there's a 5mb size limit on Mobile Safari's implementation of HTML5's application cache.
Does anyone know how to circumvent or raise this? Is there some unexposed meta tag that I should know about? I have to cache some video content for an offline app and 5mb is not going to be enough.
Only thing I can think of is to mod more memory to the phone. Local storage on mobile is a laughable concept, they're not full-blown computers and most of them aren't even "smart".
(This is purely an opinion but I'm very much willing to take any and all the reputation hit for it.)
Late edit: A bit further clarification, consider iPhone: Its browser allows the user to open up to 8 tabs at any time. It's first models has 128MB of RAM and newer models have 256MB of RAM. Now, allowing 5 megabytes per tab and 8 tabs mean that just the cached content may take up to 40 megabytes of those precious bits which is already quite a lot since I really doubt that the browser itself, not to mention phone's OS and other stuff hanging in memory wouldn't take a significant part of the memory already.
On top of that as long as even a single old-generation iPhone exists, Apple has to support it on software - it wouldn't be good for the image of the company (not that it'd be that great at all anyway currently) if some of their everyday products would just stop working all the sudden.
In short, it's just not feasible to allow local storage to expand beyond a few megabytes because phones just aren't capable to do that. Wait a couple of years and then maybe...
What else is on the page?
These guys keep their pages under the limit by either splitting up the pages or replacing some of the cached images with links:
http://www.mobilenoter.com/blog/post/2010/04/06/Removing-size-limit-of-a-page.aspx
Not sure why every forgets about the good 'ol Web apps (remember these guys? they were around before native apps!), but they're already "offline ready," which means that you don't need to load up your application cache with every component of your app.
To the best of my knowledge, there is no limit to the size of web apps.
I am trying to make a little animation player. The 5MB limit is not what is bothering me, but it is the inability to free up memory that you have already used. For example, if I load some images and display them, can I not release them afterward in order to load more? I am seeing a ~5MB limit even though I am deleting the image references. Why is that? It seems like all images are always being retained.
Thanks Bob
In my experimentation, I found that setting an IMG element's src attribute to "" or to a 1x1 gif or something does release the memory used by the original image.