Hi @ipapoutsidis,
Here is what I have done to achieve this:
On my OnStart property:
Set(varTime, Text(Now(), "hh:mm:ss"));
I have a label that is set to VarTime.
A timer control with the following properties configured:
Duration: 1000
Auto Start: true
Repeat: true
And for your button Visible property, I have:
TimeValue(varTime) > TimeValue("07:00:00") && TimeValue(varTime) < TimeValue("21:00:00")
Please note that the timer control will only start when previewing/playing the app. It will not work if you are just holding the alt key in the app studio mode.
Please tick Accept as solution if the answer is useful.
Thanks,
@AARON_C