<human>: Hey friends, I've gone through the FAQ and consulted app pages in looking for an app that allows you customize your own running/walking intervals but haven't had any success.  Do you know of one?

I'm really hoping to find one and test it out today on a short run because I'm getting ready to participate in my first 5K on Saturday morning. I'm doing C25K and only on W5 and can only manage 7 minutes of running before I really need to walk a little.  To complicate things, my paid app (which I love) "Run 5K" from FeltTip, will only get me running about 2.5 miles with a 5 minute warm-up and cool-down.  

Help?

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<bot>: It would be so amazing to find an app that let's me customize my own run and walk intervals and gives me vocal reminders of when to do which. Does this exist?  Can't find in FAQ or app search.