Rapid development of Cloud Computing and its increasing popularity in recent years has driven many commercial cloud providers in the market. Cloud service providers have a lot of heterogeneity in the resources they use. They have their own servers, different cloud infrastructures and APIs and methods to access the cloud resources. Lack of standards has caused the collaboration and portability of cloud services a very complex task. In this paper we have identified the challenges involved in portability of cloud apps and analyzed the existing techniques for portability at platform level. In this paper, we propose an approach using Model Driven Engineering to develop SaaS applications in a cloud-agnostic way. We introduce DSkyL, an eclipse plugin for cloud application development using feature models and domain model analysis, which would support construction, customization, development and deployment of cloud application components across multiple clouds. It also reduces the application development time drastically. This paper aims to sketch the architecture of DSkyL and the major steps involved in the process.