Research in Motion has shot down a wild rumor that its BlackBerry messaging app would be available on iOS starting April 26.

The rumor started Tuesday night when a poster at the MacRumors forums said she had attended a social media conference in Toronto with RIM’s chief executive, Jim Basillie, and that he promised the messaging platform was headed to Apple’s iOS next month.

The problem? There was no conference. RIM told Boy Genius Report, “RIM did not hold a conference in Toronto this week, and Jim Basillie did not speak at any event in Toronto this week.”

Well. That’s pretty definitive.

Boy Genius Report reported earlier this month that BlackBerry Messenger is due to hit Android before the year is up and will eventually make its way to iOS. It stands by that claim, but says it’s just not happening next month. According to that earlier report, the Android and iOS versions would be stripped-down versions of the current messaging platform. RIM did recently announce that its upcoming BlackBerry PlayBook will be able to run Android apps. The Android and iOS versions would be able to send messages but not send photos or location info.

BlackBerry users: Would you abandon your phones if BBM went to other platforms? Non-Blackberry users: Would you download the messenger for you phone?

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