That's not a great business model. They should have devices that either scale with you, or different models with feature-sets that target different ranges of users.

The people that are active and stick with fitness tracking are exactly the ones that are most likely to purchase new devices over time - either as replacements or upgrades. Instead, they switch to Garmin or some other more "serious" fitness tracker. That's a crying shame for Fitbit... the original fitness tracker.

Supporting chest-straps, or selling their own chest-strap, doesn't mean a casual users needs to buy one. But it does mean a growing serious fitness enthusiast can continue to use Fitbit, buying new devices over time.

From my experience, Fitbit still has the most polished App. It's a darn shame you can't get more out of Fitbit devices though.