When I first started all this , I very quickly found "Runkeeper" and used it for the duration of C25K - and used it for quite a long time afterwards. Then it seemed to become slower and slower to use on my phone - and finally when I got to version 5.2.7 for Android, the very next "update" broke it for me - I could no longer get AUDIO CUES - reverting back to 5.2.7 got it going again , but as I said, not so fast!! I have been using it that way for several months now.
BUT - a few days ago, I noticed that the latest version was now 188.8.131.52 - so I completely uninstalled the programme and reinstalled it ( that is, I didn't just simply accept an update , but uninstalled/reinstalled completely)
A complete revelation!!!! It is running perfectly now and seemingly smoother and faster than ever before -- I am a happy chappy again!!!