Better timer than delay() ?

Hello ;

I am currently doing a project related to the pandemic and i need help figuring out a better way do to a timer than delay()

I want to be able to send stuff via bluetooth while a timer runs ( form about 20 mins to an hour)

What is a good library / technique to do that ? Thanks

See Using millis() for timing. A beginners guide, Several things at the same time and the BlinkWithoutDelay example in the IDE

See also: how to use millis() instead of multiple delay()

If you're waiting for the bluetooth stuff to complete, why do you need to time it? Or, are you thinking that you want to send stuff every 20 min to an hour?

-jim lee