I need an iOS and android app built to take a picture of a users thigh and estimate a proper size

this app is for the site [login to view URL] it is to determine a users thigh size to recommend a product size to purchase. I also was thinking of how to achieve the best measurements and was researching a lot of existing apps on the market. My thoughts based on what is there and experience with customers measurements are as follows: - If the measurements will be done on the photo taken - then it has to be just hips area from the front and hips area from the side. Two measurements of the largest part of the thighs. -When front photo is taken - on the screen there should be crotch area pointer to align with - something like below (sorry, I could not find a better pic of it :( ) . It could be just a small angle. On the pic below waist is also shown but focus could be on the lower part - just 1-2 inches below. Ideally front thighs measurement should be done 2" below the inner crotch line - just where this picture ends. - Then on the side photo with both legs aligned - also on the same level of 2" below crotch area. - Photos can be taken when the cell phone is put on the counter top edge (usually standard height) - then the length will be more or less the length of the arm. -We can also ask to calibrate with either credit card or coin (like most of apps do).