B4J Question Advice on new app (Employee Attendance)

[mcqueccu]

I am about to work on a small B4J application - Attendance logging for the time in and time out.
The organization has about 15 employees. Also, the application is expected to work offline, and on a single machine.

My concern is If I use system time for the logs, it is possible for some employees to figure out by changing the system time backwards before logging for the system to pick their time?

My question is:
1. Is there any other system time I can access which cannot be changed by just changing system clock?

2. If no to above, is there any other way I can use to detect if someone has tempered with the date and time during the app use?

3. Can I run app in background (something like Service in B4A) which I can use to set my own time and date within the application?

 

[Erel]

Getting the time from a SNTP server: https://www.b4x.com/android/forum/threads/b4x-sntp-class.86088/#content

Is there any other system time I can access which cannot be changed by just changing system clock?

Not locally.

If no to above, is there any other way I can use to detect if someone has tempered with the date and time during the app use?

You can check the current time every second with a timer.

Can I run app in background (something like Service in B4A) which I can use to set my own time and date within the application?

You can run an app in the background. It will not be difficult to kill it with task manager.