For many scientific visualization problems such as particle simulations in astronomical data it is helpful to be able to view and explore a 3D environment/dataset; a lot of information can be derived from these visualizations. In addition to Virtual Reality approaches and other stereoscopic visualization settings such as the CAVE by Cruz et al., people are also starting to explore the interaction using 2D touch-sensitive displays. We analyze four different interaction methods and identify several concepts. A concept is an abstract description of a certain way of interaction; e.g., camera manipulation or object manipulation. Our research focuses on the similarities and differences of these concepts. The aim is to identify specific challenges and evaluate how these are addressed in the different interaction methods. The result of our research is a list of heuristics that can be applied to 3D interaction on 2D touch displays; i.e., which concept works well in certain situations and why.