A system comprising: a user-image obtaining module to obtain a user-image of a user of an electronic device; an image-mask generator to generate a user-mask image that corresponds to said user-image processed to exclude background image-data of said user-image; a product-mask generator to receive a product-image of a particular product, and to generate from said image a product-mask image that corresponds to said product-image processed to exclude background image-data of said product-image; and a user-and-product combination-image generator to receive said product-mask image and said user-mask image, and to generate from them a combined user-and-product image that depicts said user engaging with said product for virtual dressing; wherein said product is a clothing article; characterized in that said system further comprises a gravitational effect generator configured to use a gravitational effect module to estimate an effect of gravity on the combined user-and-product image by: modifying the combined user-and-product image to reflect an effect of gravitational force on a particular portion of said clothing article, by causing portions of the clothing article to appear to be dropping down due to gravity, and by modifying sleeves of said clothing article to drop down or to have lower edges, to thereby generate a more realistic look of the combined user-and-product image; wherein the gravitational effect generator is configured to take into account how gravity is estimated to affect each particular region or portion of the clothing article, and not just the entirety of the product; wherein the gravitational effect generator is configured to estimate the effect of gravity on whether the clothing article would be immediately adjacent to a body part or spaced apart from said body part, to estimate how form fitting or non-form-fitting each region of the clothing article is, and to take into account a recognized shape or style of the clothing article in order to differently estimate the effect of gravity on each clothing article. a user-image obtaining module to obtain a user-image of a user of an electronic device; an image-mask generator to generate a user-mask image that corresponds to said user-image processed to exclude background image-data of said user-image; a product-mask generator to receive a product-image of a particular product, and to generate from said image a product-mask image that corresponds to said product-image processed to exclude background image-data of said product-image; and a user-and-product combination-image generator to receive said product-mask image and said user-mask image, and to generate from them a combined user-and-product image that depicts said user engaging with said product for virtual dressing; modifying the combined user-and-product image to reflect an effect of gravitational force on a particular portion of said clothing article, by causing portions of the clothing article to appear to be dropping down due to gravity, and by modifying sleeves of said clothing article to drop down or to have lower edges, to thereby generate a more realistic look of the combined user-and-product image; wherein the gravitational effect generator is configured to take into account how gravity is estimated to affect each particular region or portion of the clothing article, and not just the entirety of the product; wherein the gravitational effect generator is configured to estimate the effect of gravity on whether the clothing article would be immediately adjacent to a body part or spaced apart from said body part, to estimate how form fitting or non-form-fitting each region of the clothing article is, and to take into account a recognized shape or style of the clothing article in order to differently estimate the effect of gravity on each clothing article.