If you would go with either of them you would be making a good choice...
Here on TE you would get different advices... some would advice you to buy S II and some would advice you to buy iPhone 4...
Hardware specs wise S II is light years ahead than iPhone 4 (or the correct term would be 1 year ahead
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)... You mentioned that you want to buy a phone for browsing... Then IMO you should buy S II coz it supports HSDPA upto 21.1MBPS and the android browser comes with Flash support... To be honest i have iPod Touch 4G... i use it for listening music aswell as for browsing... i really get angry when some youtube videos doesn't play on iPod touch coz it doesn't support Flash...
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... The reviewer of engadget who reviewed Galaxy S II said that the "Super AMOLED Plus Display that S II has is better than iPhone Retina Display even though it has
lesser resolution 960x540 to be specific whereas iPhone 4 display resolution is 960x640"... If you are gonna watch a lot of HD videos and gonna do browsing stuff then S II 4.3inch display is really gonna come in handy... And S II also supports more video formats out of the box as compared to iPhone 4... S II supports H.264, Xvid and DivX out of the box whereas iPhone only supports H.264... You can play Xvid videos on iPhone too but for that you either have to buy third party apps or you have to jailbreak the iPhone 4 to install pirated apps for free... the S II has dual core processor so the browsing experience would be silky smooth... I think i have said enough things against iPhone 4... Now i would say the good things
Apple iPhone 4 is great if you are looking for a simple user interface phone... has great retina display, iPod on board and millions apps out there to download... Apple pushes updates more often then what we get to see from google's side... Apple is capable of introducing two three models per year but the way they design and produce their new products is simply great... What google do google releases a new Android update and then all the mobile manufacturing companies joins the race to port the new update to their cellphones... some companies becomes successful to do so after some months... but some companies struggle to do so because either of their handset incapability or because of their inability to port all the new updates on time... If you would check iPhone 3GS is still receiving updates... So its on you... Decide whether you want a phone with better hardware or a phone with better software support...