I`ve just released a new app at Google Play store. :)
Walk Run is focused on helping runners that use interval training to improve. The user can configure it's training by setting the duration of each step (warm up, run, walk and cooldown), and the number of cycles Run/Walk he plans to perform. After that, when starting the training, a screen is displayed with the progress of the training, and a custom notification will be available so the user doesn't need to unlock the phone to see in which step he is or how much time is left to end the step. Also, the app makes the smartphone vibrate to inform the user when it is time to start running/walking/etc.
Looks simple, huh? That's the spirit. I've tried to make a user flow which is pretty straight-foward and used distant colors to represent each step, so a that a glance on the notification is enough for the running person to get the info he needs.
The app is available at https://play.google.com/store/apps/details?id=br.com.dgimenes.walkrun
It is monetized through ads (Appodeal), and I'm planning on having a "premium" plan (one time in-app purchase) soon. The backlog for the product is big, but as this is not my priority now, it should take a while to see new versions of it after v1.1 (which is planned to go live next week).