

Seriously, this. The things are genuinely useless. They can’t even measure your heart rate correctly (seriously look it up. They use algorithms to “estimate” your heart rate. Different brands give different results. People wear elaborate chest strap setups to try and get an accurate value and even then it’s subject to a huge margin of error).
Get a $10 dumbwatch with a stopwatch function. Run or cycle a familiar route once in a while to track your progress. Find different ways to challenge yourself. Do some runs all out. Hill sprints. Do some longer runs a bit slower than you would think, so that even if your breathing is a little heavier you could still hold a conversation with someone while maintaining that pace.
Ignore all the senselessly overcomplicated 5 stage heartrate zone V02max aerobic astrology bull that these companies advertise to you as a big benefit of their product. Having a 3d map of your route is not going to make you a better runner. Having a virtual leaderboard where 99% of people you compete against are using a wonky cellphone gps that teleports them 1000ft off course isn’t going to make you a better runner
I do trail running primarily these days so my actual distance I’ll just pull from the trail map.
If you do roads you can actually just drive the route in a car once, and use the trip function. You can also plan a route with a map or map app.
But the other, easiest thing to do would be to actually switch training paradigms from distance to time. Right so instead of running a 12k, or hitting 50km per week, you could say “On this training day I want to run at a tough but manageable pace for an hour, and I want to train 6 hours a week in general”
From there you just mix in some track days (or days you run any familiar route with a known distance) to get an idea of how far you might be running in those intervals of time, if you feel like you really need to.
You have to remember portable gps tech is an extremely recent thing compared to how long runners have been training. I’m not against progress for progress’s sake mind you but I just genuinely don’t believe the introduction of these apps and trackers, with their many flaws, has improved the quality of people’s training. The old ways also cost nothing and have no privacy or security risks which is a bonus for many people