The user of the application, if he wants, adds his data, and then anyone who needs a specific blood group can contact him, or the user searches for the blood group he wants, with the ability to locate his site to facilitate the search process.Through the application, you can modify your data, as you can specify the time when people can communicate with you, modify the date of your last donation, and you can also modify your status if you can donate so that you can be contacted or not.