How user can use the application:
In this project, we use firebase for the hold user datas and process them. 
In sign up part user writes name, email and password. 
Firebase keep this datas and if the user wants to login to app, it checks the mail and password and 
redirects to  home page or displaying error. In home page it displaying the welcome 'username' top of the page 
and 'username' is  being getted from data in the data  which whoever login this app now. At the top of the page,
 we have date picker and user can choose date from there. In home page also we can see the plans and  
 there are images for each plan. If we want to maximize these images we can 'Long Press' and to back original view  
 we can 'Double Tap'. Also there are clickable checkboxes in this page. User needs to choose one plan from there 
and then can make submit. If there is no clicked plan, there will be toast massage which it say 
'you need to choose one plan'.