Congrats on launching and on the great name.

I'd suggest auto tabbing when users fill out an hour e.g Entering "7" in the hours field should auto-tab to minutes field. Entering "30" into minutes should auto-tab to the next field.

Also, I would default the break deduction to 0:00 so that the time can calculate automatically when the start & end times are filled in.

Oh, also I noticed that you have a great network of useful utilities.

For SEO, I'd recommend creating a categorized utility directory (even if it is static) where you first list your own utilities and then charge other utility creators to list their own utilities. It will allow your apps to get lots more organic visibility and build a community of like-minded indiehackers.