A process for genotyping single cells having a phenotype of interest comprising: - providing a plurality of reservoirs, and a) for a plurality of reservoirs, providing, for each reservoir, at least one barcode sequence and at least one dye, wherein the at least one barcode sequence is associated with the color and the concentration of said at least one dye, and taking an image of the array thereby mapping the color and the intensity of the at least one dye for each reservoir; and b) for a plurality of reservoirs, providing, for each reservoir, at least one single cell and performing for each reservoir a phenotypic assay on said at least one single cell, and taking an image thereby mapping the phenotype of said at least one single cell for each reservoir; wherein step a) is performed before step b) or step b) is performed before step a); then c) for a plurality of reservoirs, linking, for each reservoir, the phenotype of a single cell obtained in step b) to the color and the intensity of the at least one dye obtained in step a); and - for a plurality of reservoirs, reverse transcribing, for each reservoir, nucleic acids of said at least one single cell, to obtain single cell cDNA barcoded with said at least one barcode sequence which is associated with the color and concentration of the at least one dye; and - linking the genotype with the phenotype of said at least one single cell, wherein the process is a microfluidic process comprising a step of providing a microfluidic device comprising a chip comprising at least one microfluidic channel and a plurality of reservoirs, wherein, for each reservoir, the at least one single cell is provided in a single cell droplet, wherein at least one single cell droplet is moved into one reservoir of said plurality of reservoirs by buoyancy. - providing a plurality of reservoirs, and a) for a plurality of reservoirs, providing, for each reservoir, at least one barcode sequence and at least one dye, wherein the at least one barcode sequence is associated with the color and the concentration of said at least one dye, and taking an image of the array thereby mapping the color and the intensity of the at least one dye for each reservoir; and b) for a plurality of reservoirs, providing, for each reservoir, at least one single cell and performing for each reservoir a phenotypic assay on said at least one single cell, and taking an image thereby mapping the phenotype of said at least one single cell for each reservoir; wherein step a) is performed before step b) or step b) is performed before step a); then c) for a plurality of reservoirs, linking, for each reservoir, the phenotype of a single cell obtained in step b) to the color and the intensity of the at least one dye obtained in step a); and a) for a plurality of reservoirs, providing, for each reservoir, at least one barcode sequence and at least one dye, wherein the at least one barcode sequence is associated with the color and the concentration of said at least one dye, and taking an image of the array thereby mapping the color and the intensity of the at least one dye for each reservoir; and b) for a plurality of reservoirs, providing, for each reservoir, at least one single cell and performing for each reservoir a phenotypic assay on said at least one single cell, and taking an image thereby mapping the phenotype of said at least one single cell for each reservoir; wherein step a) is performed before step b) or step b) is performed before step a); then c) for a plurality of reservoirs, linking, for each reservoir, the phenotype of a single cell obtained in step b) to the color and the intensity of the at least one dye obtained in step a); and - for a plurality of reservoirs, reverse transcribing, for each reservoir, nucleic acids of said at least one single cell, to obtain single cell cDNA barcoded with said at least one barcode sequence which is associated with the color and concentration of the at least one dye; and - linking the genotype with the phenotype of said at least one single cell,