Look into the Xiaomi MiBand 4 / 5, they're around $30. Battery life can last 2-3+ weeks with litte heart rate monitoring. Sleep tracking is there, but I can't c

Look into the Xiaomi MiBand 4 / 5, they're around $30. Battery life can last 2-3+ weeks with litte heart rate monitoring. Sleep tracking is there, but I can't comment on it's accuracy, although it should be pretty good. It's better than Fitbit in every category, and significantly cheaper. There's plenty of 3rd party app support and it's easy to extract data into a privacy conscious health app, if you don't trust any of the apps too.