How my Couch to 5K app came about
Couch to 5K (or C25K for short) is a workout program which takes 9 weeks and starts out by having you run or jog short intervals followed by walking recovery intervals.
The idea to make this an iPhone app came from Kasten, who was using a podcast by Robert Ullrey based on the Couch to 5K program on CoolRunning.com. Using the podcast meant that she was stuck with the music included in the podcast, and she wanted to play her own music while still getting the cues to start and stop running.
Kasten is a painter, artist, designer, and musician in Philadelphia. She was a beta tester for my Food Diary Calorie Counter iPhone app. She and I worked on the graphic design of my Tuna Pitch chromatic tuner app. On April 12th, while I was working with her on the graphics, she emailed me an idea for the Couch to 5K app she had while running. We both use the Nike Plus system for recording our miles and sometimes have competitions to see who can run the most miles in a month.
It's not unusual to work on several projects at the same time, and I started working on my Couch to 5K workout app while I was finishing up my Tuna Pitch app. First thing I did was download an existing C25K app, and I was disappointed with the graphics and UI. I wanted to be able to pick any of the 27 workouts and start or resume my program from the middle, and to be able to look ahead and see how hard the next few workouts would be. I also wanted an app that would still work if you turned off the iPhone's screen.
And finally, I wanted an app that's visually more interesting, after seeing the wood grains in apps such as Groceries and Delicious Library. I found several free wood grain patterns by Sue Chastain, and did some Photoshop magic to put wood grain on what was initially a very plain white wireframe.
Testing the workout app meant actually going out and doing a 30 to 40 minute workout in the streets of New York City, with all the traffic noise and other distractions of a busy city. I could only do a full test on myself once a day, because I needed to rest between runs. I did test it at my desk to make sure it still ran when the screen was locked and to test other parts of the app, but nothing beats actual field tests, or in my case, city tests.
Kasten also tested the app as it was being developed, and provided lots of valuable feedback. We had a problem with the audio cues (for when to start and stop each interval) were not audible above the music, and there is no way to control the volume coming from the iPod music player, so you can't duck the music to make your own alert sound more audible. We made the iPhone vibrate during the cues, but the iPod touch doesn't have that feature, so we had to do more. The cues originally had single-tone beeps, but with some electronic music it could be mistaken for part of the original composition, so they were changed into rising or descending tone sirens with some distortion added for harmonics. The voices were also compressed and amplified so they clipped by +3 decibels.
Collaborating with Kasten was fun. Kasten did the female voice in the app, and I did the male voice. I created the siren alarms and beep sounds in Sound Studio 3. There's also a drawing of a Bacon Heart that Kasten made on Valentine's Day. You can see it briefly in the background when you flip between the front and Settings sides of the app.
On May 19th, 2009 at 11:00 pm, I submitted the app to the iTunes App Store, and at 8:43 pm on May 26th the app was approved.