Scalar WIMP are somewhat less popular than their fermionic counterparts. Yet, they have specific and interesting phenomenology and are rather well-motivated, at least from a bottom-up perspective to the dark matter particle problem. In this talk, after a personal perspective on some dark matter model building aspects, I will discuss in details the phenomenology of some very simple scalar WIMP candidates (i.e. the scalar 7-plet minimal dark matter candidate and a real scalar through the so-called vector-like portal), with a focus on their possible indirect detection through searches for gamma-ray spectral features