So I book my working time every day with my smartphone after leaving the office. It works very well for me via the browser.

Especially when entering via the browser on a smartphone (small screen), the screen display at least for me (iOS, Edge) is very limited and input is not easy. In my opinion, an app or a browser display optimized for smartphone size would be useful for recording time on the go.

Personally, I like the flexible use of the browser at any time for all devices and even without installation and prefer that at any time of an app that often only calls up a browser in the background and the mobile website anyway. The only thing that could possibly be nice about it is that you could also solve the password entry biometrically and therefore more conveniently.