III-V semiconductor whispering gallery mode (WGM) microdisks have many assets for second order nonlinear optics. Their large nonlinear susceptibility combined with their high refractive index allows us to consider low power optical function based on nonlinear effects in a broad spectral range. In this paper, we will review our recent results on WGM GaP microdisks. We will present our experimental results on Q-factor characterization and second harmonic generation measurements under modal 4 phase matching. We will also review some phase-matching schemes propositions based on antiphase boundary engineering. Finally, we will discuss other device configurations based on coupled microdisks.