I'm developing a web app to help with controlling your workout sessions. You can create your trainings and log your development. You have also a chronometer for your convenience, helping to control the exercise and cooldown times.
The Beta version is already available at https://workout.jadelabs.com.br/.
The pending topics are currently:
to enable editing the list of exercises
to create some charts with the training development
to enable export a CSV of the training logs
to create relevant functionalities requested by my supporters
Test it out, it's free. I hope you enjoy it.