New ads—lots of new ads—are on their way to Twitter. Hoping to win over e-commerce companies and mobile-game developers, the communications platform will debut 15 types of new ad products and improved ways to target users over the next six months, according to people familiar with the company’s plans. The first batch will be released in a few weeks and will include a product that will coax users to download apps through Twitter, these people said. Over the past year, some consumer brands have thrown more advertising dollars toward Twitter, especially during live events such as the Super Bowl or Academy Awards. Twitter’s simple suite of promoted advertising products—a trio of ads that target select users and receive preferential placements as tweets, trends and recommended accounts—haven’t resonated with mobile game and e-commerce companies whose advertising decisions are driven by app downloads, subscriber sign-ups and purchases.