Offline iOS web app: loads my manifest, but doesn't work offline

Question

I\'m writing a web app to be used offline on iOS. I\'ve created a manifest, am serving it up as text/cache-manifest, and it usually works fine, when running in

Answer 1

I've written an offline app that still seems to work in 4.2 and 4.2.1; the post is a little dusty, but the code still runs:

http://kentbrewster.com/backchannel/

Remy Sharp has a newer post with code that also works, here:

http://remysharp.com/2011/01/31/simple-offline-application/

His app:

http://rem.im/boggle/

Answer 2

I have one potential workaround for this - it seems a bit crazy, but here goes... I work with the cache.manifest and full screen apps a lot (here's a test if you need: http://www.mrspeaker.net/2010/07/12/argy-bargy/ - add to home screen then turn on flight mode and it launches - at least, as of iOS 4.2.1)

One weird thing I found is that sometimes it seems that some kind of "meta" information in files can mess them up from being cached - Have you ever noticed that in bash that if you do a "ls" some files (depending on your colour settings) are highlighted for no apparent reason? Files can have meta data that the operating system (I think) adds automagically - and there are ways to remove it... I can't remember why but here's some more details: Strip metadata from files in Snow Leopard

After tearing my hair out one day - and refusing to give up because I knew it SHOULD have worked... Chrome was saying it loaded all the files, but ended with a generic error. In the end I recreated the project structure with blank files and copy/pasted the contents over. It worked - started caching as it was supposed to!

When I looked at the files I noticed there was some meta info. I tried scrubbing this info and the original project worked again. I'm not sure this was the reason it worked again - perhaps it was just a coincidence.

Because it worked, I didn't think too much about it. The same problem happened again some months later and the copy/paste trick worked again. I was busy, so I didn't investigate further - but vowed I would get to the bottom of it the next time it happened.... but I haven't had to yet.

Phew. Anyway, glad I got to write that down somewhere...

[UPDATE: months and months later - I've not been able to reproduce this, so I don't think it's the metadata]

Answer 3

I have several working offline and on/offline web apps.

When I turn off airport mode, I get a request for the manifest and some other files.

I don't get requests for images, JavaScript, CSS or cached AJAX files.

If you see requests for your resources, IOS doesn't have them cached.

Safari in general is more picky with manifests.

I suggest you try Safari on your computer.

Answer 4

I have run into the same problem today on iOS 4.3. I was able to fix the problem by adding a favicon.ico file and also adding it to the manifest.

Answer 5

No offline web app (as of iOS 4.2) can run without an internet connection (which means Airplane mode, too) when using <meta name="apple-mobile-web-app-capable" content="yes" /> in the html head section. I have verified this with every example I've seen and the ones that use Safari to render the site work fine, but when you throw in that meta tag, it won't work. Try your app without it and you'll see what I mean.

Answer 6

I've written an app and it works fine through the mobile browser, but when adding the desktop... Doesnt work. I guess apple have given up on IOS4 and all efforts are now on OS5. Shame :(