Leading Facebook in-app advertiser Lifestreet has announced a new self-service portal to enable mobile developers to serve performance-based display ads within their apps. The platform offers ads that earn revenue on a cost-per-install (CPI), cost-per-acquisition (CPA), or cost-per-engagement (CPE) basis. Lifestreet paid out $150 million to approximately 3,500 Facebook developers last year. [Source: TechCrunch]