Opera's mobile Web browser was cleared for the iPod and iPhone early last month and it has already become a top platform for Opera Mini. The Norwegian software company said in its State of the Mobile Web Report that a million App Store customers downloaded the alternative browser in the first day alone, and soared to more than 2.6 million by the end of April.

Opera Mini's user base reached 58.9 million, up 6.6% from the month prior and over 152% year-over-year. Page views climbed to 26.3 billion, up 1.6% sequentially and 203% on-year. That response made the iPhone the most popular Opera device in the US, passing BlackBerry phones, and fifth in the UK.

It also pushed the United States to sixth (from eighth) in the top 10 countries by usage, and the iPhone became the third most popular handset in the world to use Opera Mini, behind the Nokia 5130 XpressMusic and Nokia 6300. The remaining devices on the list (fourth through tenth) are all Nokias.