Time management and calculating for my employees to be signed in by email Prompt

Using this app to record time of starting and ending shifts for multi workers to save the date,time and duration of each shift and giving a report in the end of each month.it can be run offline and online by starting counting time until the mobile is connected .each shift should not be more than ten hours continously in single shift.each worker has his own profile can see his own shifts reports and editing is not allowed only by the owner which is me.
There is a space to leave a notes in each shift by worker or owner or both . The worker to sign in need to use there own email . There is a botton for start shift and end shift .