Research In Motion (RIM) kicks off a major software developers conference Tuesday as the BlackBerry maker tries to burnish its tarnished image and stop losing ground to rivals.

Training sessions for "app" creators were being held on the eve of an annual BlackBerry DevCon Americas gathering that will run through Thursday in downtown San Francisco.

Canada-based RIM packed the conference with sessions, panels, and seminars focused on building hip, fun, or functional mini-programs for BlackBerry smartphones and the company's PlayBook tablet computer.

RIM co-chief Mike Lazaridis opens the conference early Tuesday with "mobile partners and passionate enthusiasts" who will help showcase the BlackBerry platform and "what's in store" for developers.

Along with applications for taking care of business, RIM plans sessions on making games for BlackBerry and PlayBook devices to go up against iPhones, iPads, and Android gadgets in an increasingly consumer-driven market.

Apps have become vital to the popularity of smartphones and tablets as people increasingly rely on mobile devices for conveniences such as tracking jogging routes, posting updates to Facebook, or playing games like Angry Birds.

RIM stock price dropped more than six percent to $22.43 a share on the Nasdaq exchange on Monday after the company offered customers free apps to make amends for outages last week that bedeviled millions of users worldwide.

RIM said customers would be able to download for free a selection of its premium applications "worth a total value of more than $100" including games, hands-free operating programs and other tools "as an expression of appreciation."

Users will have until the end of the year to avail themselves of the offer.

RIM's network services for BlackBerry mobile phones were down intermittently for up to three days last week in western Asia, the Middle East, Africa, Europe, and North and South America.

RIM blamed the failure of a "core switch" at a facility in Europe as well as a backup mechanism for the initial problem, knocking out emails and messaging for users.

RIM has some 70 million BlackBerry subscribers worldwide, with many companies and governments depending on their networks and phones for internal communications.

The company has faced challenges from other aggressive smartphone makers, especially Apple's iPhone, though RIM's security-tight networks still remain preferred by businesses.