So, when I finished today's run, I went to the Run.GPS screen, in order to press the red button in order to conclude the training and upload the data to the server.
However, when I touched the screen, the (much larger) adjacent "distance" button was what I pressed, inadvertently. Unfortunately, this caused the data for my run to be erased, without putting up a warning screen telling me that it was doing so.
I hoped that I had simply pressed the button to create a new "lap", so I uploaded my data. But, instead of my 25-minute run, I saw that I had uploaded a 1-minute training. How disappointing!
For a better UI design approach, it might be more effective to do one or more of the following:
* make the start/stop training button larger, so it is easier to press (without mistakenly pressing another button)
* create more distance in between the stop/start training button and the distance button
* move the start/stop button to a different location in the screen, away from the distance button
* create a dialog screen to require the user to confirm that the training is being erased, after the distance button is pressed.