Can i use pilot logbook app on multi device

The ipilotlogbook application can be used by each user on one iPhone and one iPad device.

Is the airport database being updated?

The airport database is regularly updated.

Can i subscribe to the app with my apple id

In the sign up section, there is an option to sign up with an apple id.

Are day and night flights calculated?

Yes system automatically calculates day and night times.

How can i update flight time limits according to my company procedures.

You can edit flight time limits in Flight Limits page which takes place in User Setup page.