The chief executive of BlackBerry has penned an open letter to members of U.S. Congress saying app creators should be required to make their software compatible for BlackBerry devices.

John Chen wants "net neutrality," where all Internet-based companies have a fair shot at the market.

"Unfortunately, not all content and applications providers have embraced openness and neutrality," Chen wrote. "Unlike BlackBerry, which allows iPhone users to download and use our BBM service, Apple does not allow BlackBerry or Android users to download Apple’s iMessage messaging service ... iPhone and Android users are able to access far more content and applications than customers using devices running other operating systems. These are precisely the sort of discriminatory practices that neutrality advocates have criticized..." adding that app makers should be "mandated" to cover all platforms and devices.