I'm trying to find a pedometer—a small device that can fit into my pocket, or a shoe, but preferably not in my hand or around my wrist—that will be able to keep track of my steps seamlessly when I play sports, for example, without it's being connected to my phone. However, after the activity is done, I would like to be able to sync it with an app of my choice (e.g. Samsung Health). I can't seem to find such a device. Does one exist?
I don't think one exits, but you could use a smartwatch and put it in your pocket instead of wearing it. Or buying a bike computer and using it to run/walk.
But why not just use a normal phone? Google fit tracks your workout offline even when your phone is turned off or the battery is dead. The speedometer doesn't consume battery and google calculates your trajectories at 100% precision by simply registering in which direction the speedometer in the phone is turned. You could have a phone with a dead battery in your pocket for one entire week and google would count every step you take and even understand when you are actually on your feet or using a vehicle, if your phone is water proof it can also tell if you are swimming. Google is really good at tracking people.
(Not it's not some conspiracy theory, it's just something I understood after realizing that google tracked me on a phone which had no sim-card on and the battery was detached)