Here's my thoughts.
- Why should I download your app?
- Why should I run my phone GPS and run my battery down?
- Why should I click on anything before I go ride?
- Why don't you just buy the data from existing commercial apps that DO provide me with a reason to download, run GPS, and record my ride?
You just want the data, right? Just get the data. Other people are already collecting it by offering me something in return. It would be very difficult to compete with those companies.