This is the solution you're looking for, probably.

amuno.hubpages.com/hub/How-To-Install-Old-iPhone-Apps-In-IOS-3X-And-4X

If necessary, I'll mail you the Opera Mini 6 .ipa file.

Is there a way to change helper applications on opera mini 6 for ios?

For example, I'd like .zip files to be opened in iCab, not Safari, as the first has a download manager while Safari just gives an error and, more importantly, I'd like Opera to cease using the builtin OS YouTube support, as it is now broken on iPhoneOS 3, and open Youtube videos in safari (or pass them trough the server, like regular videos).

Also, would be great if opera asked for confirmation before opening another app (pretty annoying to open a page only to see opera closing and Safari opening becouse it was actually a PDF), but I guess that will never happen on this device.

Thanks!

I still use Opera Mini 6 (downloaded years ago) on my iphoneos 3 devices, while it might look mlre Spartan it offer an experience far superior to icabor safari on such dated devices, actually allowing me to perform some basic browsing.

So, for you opera mini wouldbe a great solution to most browsing activities, theonly problem is obtaining an old, compatible version these days.

Ios 4.2 offers a "last compatible version" in the app store, but if Opera doesn't provide it or you run an olderversion of the iOS you might be out of luck…MAYBE there is a way to obtain an older version jailbreaking your device (very recommended on a device that old, as you can overcomesome limitations that way), but further research would be required.