As regular readers will know, I've been waiting for the release of Opera Mini for iPhone for quite some time. Finally, Apple has approved the new web browser and it's available in the App Store from today. But having played around with it all morning I've decided not to switch to Opera Mini from Safari, despite that fact that it is better than the built-in Apple browser in so many ways.
Like I said, there's a lot of greatness within Opera Mini. It's true that pages load much quicker than they do within Safari, thanks to the way Opera compresses sites and delivers them from its own servers. It's also true that it's easier to manage all the pages you have open thanks to the stylish tabs dock that lets you quickly flick through thumbnails of the sites you have loaded. Stuff like speed dial, address auto-complete, long-click menus, password remembering, and bookmark syncing help to make it quicker and easier to access web content.

So why am I sticking with Safari then? Because the page zooming functionality in Opera Mini is utterly awful. For starters, when a page is zoomed out to full screen the text is generally so small as to be completely unreadable, which doesn't happen in the default iPhone browser. Sure, you can double tap or pinch the screen in Opera Mini to zoom in but you can only zoom in to the level set by the app. That is to say, you can't control the zoom level like you can in Safari. For me, Safari's flexible pinch zooming system is one of the main reasons the web works so well on an iPhone. Opera Mini's primitive two-level zoom (one of which is unreadable, remember) destroys this freedom and flexibility, making for a constrictive, frustrating web experience.
It's such a shame that a single poorly-executed feature can spoil what would otherwise be a must-have iPhone application.

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I don't get why people think thats a good browser. It's fast. Thats where the good stuff ends. The fonts are ugly and as you mentioned sometimes unreadable. Rendering errors are pretty common. The UI is one big joke: Big ugly buttons instead of system standards, weird zooming, slow scrolling etc. Opera Mini might be good for Symbian or Windows mobile standards. On the iPhone they have to do better. But then this is just the first release.
As you can't set anything other than Safari to be the default browser at the moment, Opera Mini would have to be absolutely incredible for me to use it regularly. As it is, I agree with James and partly with Marvin. Rendering zoomed out is awful, but the tabs are cool, as is the start page. I hope Apple take a look at the neat aspects of Opera in their next Safari update :)
It should also be noted that Apple reserve specific functions in their API (pinch functionality being one of them) for Apple software alone. Other software programmers are not allowed to use them if their software is to be used as "certified" and sold in the Apple Store.
Apple will not allow Opera on iPhone if Opera is better than Safari. The only reason I see why Opera want to make Opera on iPhone is they wanted their browser available on all platform.
FASTNESS RENDER A BUCK. FEATURES MATTER A LOT
Ithink that opera mini is fast but it should have some more features like it should give us a good help.there is not a solution for every problem,it should have a spell cheaker for opera mini websites.